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Mergesort2.java
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723 lines (594 loc) · 31.1 KB
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// public class Mergesort2 {
// private static int[] S; // Array to be sorted
// private static long totalComparisons = 0; // Counter for comparisons
// private static long grandTotalComparisons = 0; // Counter for grand total comparisons
// public static void main(String[] args) {
// System.out.println("Merge Sort Algorithm Used: MergeSort2\n");
// S = new int[]{16, 14, 5, 7, 1, 8, 12, 10, 6, 8};
// int n = S.length;
// mergesort2(1, n); // Sort the array from index 1 to n (following textbook convention)
// System.out.println("Sorted array: ");
// for (int num : S) {
// System.out.print(num + " ");
// }
// System.out.println("\n");
// // Display initial analysis
// System.out.println("Mergesort Analysis:");
// System.out.println(" Algorithm: Top-Down Recursive Merge Sort");
// System.out.println(" Total Comparisons Made: " + totalComparisons);
// System.out.println(" Time Complexity: O(n log n)");
// System.out.println(" Space Complexity: O(n)");
// // Performance testing
// int[] sizes = {10, 100, 1000, 10000, 100000, 1000000};
// long grandTotalTimeMillis = 0; // Variable to track grand total time in milliseconds
// long grandTotalMemoryBytes = 0; // Variable to track grand total memory usage in bytes
// for (int size : sizes) {
// int[][] testArrays = {
// ArrayGenerator.generateRandomArray(size),
// ArrayGenerator.generateSortedArray(size),
// ArrayGenerator.generateReversedArray(size),
// ArrayGenerator.generateNearlySortedArray(size, 0.05)
// };
// String[] arrayTypes = {"Random", "Sorted", "Reversed", "Nearly Sorted"};
// for (int t = 0; t < testArrays.length; t++) {
// int[] generatedArray = testArrays[t];
// long totalTime = 0;
// long totalMemoryUsed = 0;
// // Reset local counters
// totalComparisons = 0;
// for (int i = 0; i < 100; i++) {
// int[] arrayCopy = generatedArray.clone();
// S = arrayCopy;
// // Measure memory usage before sorting
// Runtime runtime = Runtime.getRuntime();
// runtime.gc(); // Request garbage collection
// long beforeMemory = runtime.totalMemory() - runtime.freeMemory();
// long startTime = System.currentTimeMillis();
// mergesort2(1, S.length);
// long endTime = System.currentTimeMillis();
// // Measure memory usage after sorting
// long afterMemory = runtime.totalMemory() - runtime.freeMemory();
// long memoryUsed = afterMemory - beforeMemory;
// totalMemoryUsed += memoryUsed;
// totalTime += (endTime - startTime);
// }
// long averageTimeMillis = totalTime / 100;
// double averageTimeSeconds = averageTimeMillis / 1000.0;
// long averageMemoryUsed = totalMemoryUsed / 100;
// // Add to grand totals
// grandTotalTimeMillis += totalTime;
// grandTotalMemoryBytes += totalMemoryUsed;
// grandTotalComparisons += totalComparisons;
// long minutes = averageTimeMillis / (60 * 1000);
// double seconds = (averageTimeMillis % (60 * 1000)) / 1000.0;
// System.out.println("Average execution time for " + arrayTypes[t] + " array of size " + size + ":");
// System.out.println(" " + averageTimeMillis + " milliseconds");
// System.out.println(" " + averageTimeSeconds + " seconds");
// System.out.println(" " + minutes + " minutes and " + seconds + " seconds");
// System.out.println(" " + averageMemoryUsed + " bytes of memory used");
// System.out.println(" Total Comparisons: " + totalComparisons);
// }
// }
// double grandTotalTimeSecondsFinal = grandTotalTimeMillis / 1000.0;
// long grandTotalMinutes = grandTotalTimeMillis / (60 * 1000);
// double grandTotalSeconds = (grandTotalTimeMillis % (60 * 1000)) / 1000.0;
// // Display grand totals
// System.out.println("\nGrand Total Execution Time for All Arrays and Sizes:");
// System.out.println(" " + grandTotalTimeMillis + " milliseconds");
// System.out.println(" " + grandTotalTimeSecondsFinal + " seconds");
// System.out.println(" " + grandTotalMinutes + " minutes and " + grandTotalSeconds + " seconds");
// System.out.println(" " + grandTotalMemoryBytes + " bytes of total memory used");
// System.out.println(" " + grandTotalComparisons + " total comparisons made");
// System.out.println("Merge Sort Algorithm Used: MergeSort2\n");
// }
// // Mergesort2 method, following textbook convention of indexing from 1
// public static void mergesort2(int low, int high) {
// if (low < high) {
// int mid = (low + high) / 2;
// mergesort2(low, mid);
// mergesort2(mid + 1, high);
// merge2(low, mid, high);
// }
// }
// // Merge method to merge the sorted subarrays (Algorithm 2.5)
// public static void merge2(int low, int mid, int high) {
// int n1 = mid - low + 1;
// int n2 = high - mid;
// // Create temporary arrays
// int[] L = new int[n1];
// int[] R = new int[n2];
// // Copy data to temporary arrays
// for (int i = 0; i < n1; i++) {
// L[i] = S[low - 1 + i]; // Adjust for indexing from 1 (low - 1)
// }
// for (int j = 0; j < n2; j++) {
// R[j] = S[mid + j];
// }
// // Merge the temp arrays back into S
// int i = 0, j = 0, k = low - 1;
// while (i < n1 && j < n2) {
// totalComparisons++; // Count each comparison
// if (L[i] <= R[j]) {
// S[k] = L[i];
// i++;
// } else {
// S[k] = R[j];
// j++;
// }
// k++;
// }
// // Copy remaining elements of L, if any
// while (i < n1) {
// S[k] = L[i];
// i++;
// k++;
// }
// // Copy remaining elements of R, if any
// while (j < n2) {
// S[k] = R[j];
// j++;
// k++;
// }
// }
// }
// import java.util.ArrayList;
// import java.util.List;
// public class Mergesort2 {
// static long totalComparisons = 0; // Counter for comparisons in merge
// static long totalMemoryAllocated = 0; // Counter for memory allocated in merge (bytes)
// static List<String> detailedResults = new ArrayList<>(); // For detailed results summary
// private static int[] S; // Array to be sorted
// public static void main(String[] args) {
// System.out.println("Merge Sort Algorithm Used: Mergesort2 (Textbook Reference)\n");
// int[] sizes = {10, 100, 1000, 10000, 100000, 1000000}; // Array sizes to test
// String[] arrayTypes = {"Random Array", "Sorted Array", "Reversed Array", "Nearly Sorted Array"};
// long grandTotalTimeMillis = 0; // Grand total time in milliseconds
// long grandTotalMemoryBytes = 0; // Grand total memory usage in bytes
// long grandTotalComparisons = 0; // Grand total comparisons
// for (int size : sizes) {
// int[] randomArray = ArrayGenerator.generateRandomArray(size);
// int[] sortedArray = ArrayGenerator.generateSortedArray(size);
// int[] reversedArray = ArrayGenerator.generateReversedArray(size);
// int[] nearlySortedArray = ArrayGenerator.generateNearlySortedArray(size, 0.05);
// int[][] testArrays = {randomArray, sortedArray, reversedArray, nearlySortedArray};
// for (int t = 0; t < testArrays.length; t++) {
// long totalTime = 0;
// long totalMemoryUsed = 0;
// // Reset counters for the current array type and size
// totalComparisons = 0;
// totalMemoryAllocated = 0;
// System.out.println("\nInitial " + arrayTypes[t] + " (size " + size + "):");
// printArray(testArrays[t]); // Print the initial array
// for (int i = 0; i < 100; i++) { // Run 100 times for averaging
// int[] arrayCopy = testArrays[t].clone();
// S = new int[arrayCopy.length + 1]; // Prepare 1-based array
// System.arraycopy(arrayCopy, 0, S, 1, arrayCopy.length); // Copy elements to 1-based index
// // Measure memory usage before sorting
// Runtime runtime = Runtime.getRuntime();
// runtime.gc(); // Request garbage collection
// long beforeMemory = runtime.totalMemory() - runtime.freeMemory();
// long startTime = System.currentTimeMillis();
// mergesort2(1, arrayCopy.length); // Sort using textbook-based mergesort
// long endTime = System.currentTimeMillis();
// // Measure memory usage after sorting
// long afterMemory = runtime.totalMemory() - runtime.freeMemory();
// long memoryUsed = afterMemory - beforeMemory;
// totalMemoryUsed += memoryUsed;
// totalTime += (endTime - startTime);
// }
// long averageTimeMillis = totalTime / 100;
// double averageTimeSeconds = averageTimeMillis / 1000.0;
// long averageMemoryUsed = totalMemoryUsed / 100;
// // Add to grand totals
// grandTotalTimeMillis += totalTime;
// grandTotalMemoryBytes += totalMemoryUsed;
// grandTotalComparisons += totalComparisons;
// // Add to detailed summary
// detailedResults.add("Array Type: " + arrayTypes[t] +
// ", Size: " + size +
// ", Average Time: " + averageTimeMillis + " ms");
// System.out.println("\nSorted " + arrayTypes[t] + " (size " + size + "):");
// printArray(S); // Print the sorted array (convert to 0-based for display)
// System.out.println("\nAverage execution time for " + arrayTypes[t] + " of size " + size + ":");
// System.out.println(" " + averageTimeMillis + " milliseconds");
// System.out.println(" " + averageTimeSeconds + " seconds");
// System.out.println(" Average Memory Used: " + averageMemoryUsed + " bytes");
// System.out.println(" Total Comparisons for size " + size + ": " + totalComparisons);
// System.out.println(" Total Memory Allocated for size " + size + ": " + totalMemoryAllocated + " bytes");
// }
// }
// double grandTotalTimeSecondsFinal = grandTotalTimeMillis / 1000.0;
// long grandTotalMinutes = grandTotalTimeMillis / (60 * 1000);
// double grandTotalSeconds = (grandTotalTimeMillis % (60 * 1000)) / 1000.0;
// System.out.println("\nGrand Total Execution Time for All Sizes:");
// System.out.println(" " + grandTotalTimeMillis + " milliseconds");
// System.out.println(" " + grandTotalTimeSecondsFinal + " seconds");
// System.out.println(" " + grandTotalMinutes + " minutes and " + grandTotalSeconds + " seconds");
// System.out.println(" Grand Total Comparisons: " + grandTotalComparisons);
// System.out.println(" Grand Total Memory Used: " + grandTotalMemoryBytes + " bytes");
// // Print detailed summary
// System.out.println("\nDetailed Results Summary:");
// for (String result : detailedResults) {
// System.out.println(result);
// }
// }
// public static void mergesort2(int low, int high) {
// if (low < high) {
// int mid = (low + high) / 2;
// mergesort2(low, mid);
// mergesort2(mid + 1, high);
// merge2(low, mid, high);
// }
// }
// public static void merge2(int low, int mid, int high) {
// int n1 = mid - low + 1;
// int n2 = high - mid;
// // Create temporary arrays
// int[] L = new int[n1];
// int[] R = new int[n2];
// // Copy data to temporary arrays
// for (int i = 0; i < n1; i++) {
// L[i] = S[low + i - 1]; // Adjust for 1-based indexing
// }
// for (int j = 0; j < n2; j++) {
// R[j] = S[mid + j];
// }
// // Merge the temporary arrays
// int i = 0, j = 0, k = low - 1;
// while (i < n1 && j < n2) {
// totalComparisons++;
// if (L[i] <= R[j]) {
// S[k] = L[i];
// i++;
// } else {
// S[k] = R[j];
// j++;
// }
// k++;
// }
// // Copy remaining elements of L[], if any
// while (i < n1) {
// S[k] = L[i];
// i++;
// k++;
// }
// // Copy remaining elements of R[], if any
// while (j < n2) {
// S[k] = R[j];
// j++;
// k++;
// }
// }
// public static void printArray(int[] array) {
// int limit = Math.min(array.length, 100); // Limit output to 100 elements for readability
// for (int i = 1; i < limit; i++) { // Adjust for 1-based indexing
// System.out.print(array[i] + " ");
// }
// if (array.length > 100) {
// System.out.println("... (output limited to 100 elements)");
// } else {
// System.out.println();
// }
// }
// }
// import java.util.ArrayList;
// import java.util.List;
// public class Mergesort2 {
// static long totalMemoryAllocated = 0; // Counter for memory allocated during merge
// static List<String> detailedResults = new ArrayList<>(); // For detailed results summary
// private static int[] S; // Array to be sorted
// public static void main(String[] args) {
// System.out.println("Merge Sort Algorithm Used: Mergesort2 (Textbook Reference)\n");
// // Allow setting an initial custom array for demonstration
// int[] customArray = {2679, 7481, 2801, 5558, 5353, 1605, 214, 4653, 3213, 7961};
// // Print the initial custom array
// System.out.println("Initial Custom Array (size " + customArray.length + "):");
// printCustomArray(customArray);
// // Prepare for 1-based indexing
// S = new int[customArray.length + 1];
// System.arraycopy(customArray, 0, S, 1, customArray.length);
// // Sort the custom array using Mergesort2
// mergesort2(1, customArray.length);
// // Print the sorted custom array
// System.out.println("Sorted Custom Array (size " + customArray.length + "):");
// printArray(S);
// // Performance testing with different array sizes and input types
// int[] sizes = {10, 100, 1000, 10000, 100000, 1000000};
// String[] arrayTypes = {"Random Array", "Sorted Array", "Reversed Array", "Nearly Sorted Array"};
// long grandTotalTimeMillis = 0; // Grand total time in milliseconds
// long grandTotalMemoryBytes = 0; // Grand total memory used in bytes
// for (int size : sizes) {
// for (String arrayType : arrayTypes) {
// int[] testArray = generateArray(arrayType, size);
// long totalTime = 0;
// long totalMemoryUsed = 0;
// System.out.println("\nInitial " + arrayType + " (size " + size + "):");
// printCustomArray(testArray);
// for (int i = 0; i < 100; i++) { // Run 100 times for averaging
// int[] arrayCopy = testArray.clone();
// S = new int[arrayCopy.length + 1]; // Prepare 1-based array
// System.arraycopy(arrayCopy, 0, S, 1, arrayCopy.length); // Copy elements to 1-based index
// // Measure memory usage before sorting
// Runtime runtime = Runtime.getRuntime();
// runtime.gc(); // Request garbage collection
// long beforeMemory = runtime.totalMemory() - runtime.freeMemory();
// long startTime = System.currentTimeMillis();
// mergesort2(1, arrayCopy.length); // Sort using textbook-based mergesort
// long endTime = System.currentTimeMillis();
// // Measure memory usage after sorting
// long afterMemory = runtime.totalMemory() - runtime.freeMemory();
// long memoryUsed = afterMemory - beforeMemory;
// totalMemoryUsed += memoryUsed;
// totalTime += (endTime - startTime);
// }
// long averageTimeMillis = totalTime / 100;
// double averageTimeSeconds = averageTimeMillis / 1000.0;
// long averageMemoryUsed = totalMemoryUsed / 100;
// // Add to grand totals
// grandTotalTimeMillis += totalTime;
// grandTotalMemoryBytes += totalMemoryUsed;
// // Add to detailed summary
// detailedResults.add("Array Type: " + arrayType +
// ", Size: " + size +
// ", Average Time: " + averageTimeMillis + " ms" +
// ", Average Memory Used: " + averageMemoryUsed + " bytes");
// System.out.println("\nSorted " + arrayType + " (size " + size + "):");
// printArray(S);
// System.out.println("\nAverage execution time for " + arrayType + " of size " + size + ":");
// System.out.println(" " + averageTimeMillis + " milliseconds");
// System.out.println(" " + averageTimeSeconds + " seconds");
// System.out.println(" Average Memory Used: " + averageMemoryUsed + " bytes");
// }
// }
// // Print the custom array again at the end for reference
// System.out.println("\nGrand Total Execution Time for All Sizes:");
// System.out.println(" " + grandTotalTimeMillis + " milliseconds");
// System.out.println(" " + (grandTotalTimeMillis / 1000.0) + " seconds");
// System.out.println(" Grand Total Memory Used: " + grandTotalMemoryBytes + " bytes");
// // Print detailed summary
// System.out.println("\nDetailed Results Summary:");
// for (String result : detailedResults) {
// System.out.println(result);
// }
// }
// public static void mergesort2(int low, int high) {
// if (low < high) {
// int mid = (low + high) / 2;
// mergesort2(low, mid);
// mergesort2(mid + 1, high);
// merge2(low, mid, high);
// }
// }
// public static void merge2(int low, int mid, int high) {
// int[] U = new int[high - low + 1 + 1]; // Temporary array for merging (1-based indexing)
// totalMemoryAllocated += U.length * Integer.BYTES; // Memory allocated for temporary array
// int i = low, j = mid + 1, k = 1;
// // Merge the two subarrays
// while (i <= mid && j <= high) {
// if (S[i] <= S[j]) {
// U[k++] = S[i++];
// } else {
// U[k++] = S[j++];
// }
// }
// // Copy the remaining elements of the left subarray, if any
// while (i <= mid) {
// U[k++] = S[i++];
// }
// // Copy the remaining elements of the right subarray, if any
// while (j <= high) {
// U[k++] = S[j++];
// }
// // Copy the merged array back to the original array
// for (k = 1; k <= (high - low + 1); k++) {
// S[low + k - 1] = U[k];
// }
// }
// public static void printArray(int[] array) {
// int limit = Math.min(array.length - 1, 25); // Adjust for 1-based indexing
// for (int i = 1; i <= limit; i++) { // Adjust for 1-based indexing
// System.out.print(array[i] + " ");
// }
// if (array.length > 26) {
// System.out.println("... (output limited to 25 elements)");
// } else {
// System.out.println();
// }
// }
// public static void printCustomArray(int[] array) {
// int limit = Math.min(array.length, 25); // For 0-based indexing
// for (int i = 0; i < limit; i++) {
// System.out.print(array[i] + " ");
// }
// if (array.length > 25) {
// System.out.println("... (output limited to 25 elements)");
// } else {
// System.out.println();
// }
// }
// public static int[] generateArray(String type, int size) {
// int[] array = new int[size];
// switch (type) {
// case "Random Array":
// for (int i = 0; i < size; i++) array[i] = (int) (Math.random() * 10000);
// break;
// case "Sorted Array":
// for (int i = 0; i < size; i++) array[i] = i;
// break;
// case "Reversed Array":
// for (int i = 0; i < size; i++) array[i] = size - i;
// break;
// case "Nearly Sorted Array":
// for (int i = 0; i < size; i++) array[i] = i;
// for (int i = 0; i < size * 0.05; i++) array[(int) (Math.random() * size)] = (int) (Math.random() * 10000);
// break;
// }
// return array;
// }
// }
import java.io.BufferedWriter;
import java.io.FileWriter;
import java.io.IOException;
import java.util.ArrayList;
import java.util.List;
public class Mergesort2 {
static long totalMemoryAllocated = 0; // Counter for memory allocated during merge
static List<String> detailedResults = new ArrayList<>(); // Detailed results for summary
private static int[] S; // Array to be sorted
public static void main(String[] args) {
System.out.println("Merge Sort Algorithm Used: Mergesort2 \n"); // Display the algorithm used
// Custom array for demonstration
int[] customArray = {44, 7481, 23, 1111111, 0000004, 0005005, 214, 43, 13, 7961}; // Custom array
System.out.println("Initial Custom Array (size " + customArray.length + "):"); // Display the initial array
printCustomArray(customArray); // Print the initial array
// Prepare for 1-based indexing
S = new int[customArray.length + 1]; // Prepare 1-based array
System.arraycopy(customArray, 0, S, 1, customArray.length); // Copy elements to 1-based index
// Sort the custom array using Mergesort2
mergesort2(1, customArray.length);
System.out.println("Sorted Custom Array (size " + customArray.length + "):"); // Display the sorted array
printArray(S);
// Performance testing with different array sizes and input types
int[] sizes = {10, 100, 1000, 10000, 100000, 1000000}; // Array sizes to test
String[] arrayTypes = {"Random Array", "Sorted Array", "Reversed Array", "Nearly Sorted Array"}; // Array types
long grandTotalTimeMillis = 0; // Grand total time in milliseconds
long grandTotalMemoryBytes = 0; // Grand total memory used in bytes
try (BufferedWriter writer = new BufferedWriter(new FileWriter("Mergesort2_Results.txt"))) { // Write results to file
writer.write("Detailed Results:\n"); // Write detailed results to file
for (int size : sizes) {
for (String arrayType : arrayTypes) { // Iterate over array types
int[] testArray = generateArray(arrayType, size); // Generate array of specified type and size
long totalTime = 0;
long totalMemoryUsed = 0;
System.out.println("\nInitial " + arrayType + " (size " + size + "):"); // Display initial array
printCustomArray(testArray);
for (int i = 0; i < 100; i++) { // Run 100 times for averaging
int[] arrayCopy = testArray.clone(); // Clone the array
S = new int[arrayCopy.length + 1]; // Prepare 1-based array
System.arraycopy(arrayCopy, 0, S, 1, arrayCopy.length);
// Measure memory usage before sorting
Runtime runtime = Runtime.getRuntime();
runtime.gc(); // Request garbage collection
long beforeMemory = runtime.totalMemory() - runtime.freeMemory();
long startTime = System.nanoTime();
mergesort2(1, arrayCopy.length); // Sort using textbook-based mergesort
long endTime = System.nanoTime();
// Measure memory usage after sorting
long afterMemory = runtime.totalMemory() - runtime.freeMemory();
long memoryUsed = afterMemory - beforeMemory;
totalMemoryUsed += memoryUsed; // Add to total memory used
totalTime += (endTime - startTime);
}
long averageTimeNanos = totalTime / 100; // Calculate average time in nanoseconds
double averageTimeMillis = averageTimeNanos / 1_000_000.0; // Convert to milliseconds
double averageTimeSeconds = averageTimeMillis / 1000.0; // Convert to seconds
long averageMemoryUsed = totalMemoryUsed / 100; // Calculate average memory used
// Add to grand totals
grandTotalTimeMillis += totalTime / 1_000_000;
grandTotalMemoryBytes += totalMemoryUsed;
// Add to detailed summary
String result = "Array Type: " + arrayType +
", Size: " + size +
", Average Time: " + averageTimeMillis + " ms (" + averageTimeSeconds + " s)" +
", Average Memory Used: " + averageMemoryUsed + " bytes";
detailedResults.add(result);
// Write to file
writer.write(result + "\n");
System.out.println("\nSorted " + arrayType + " (size " + size + "):");
printArray(S);
System.out.println("\nAverage execution time for " + arrayType + " of size " + size + ":");
System.out.println(" " + averageTimeMillis + " milliseconds");
System.out.println(" " + averageTimeSeconds + " seconds");
System.out.println(" Average Memory Used: " + averageMemoryUsed + " bytes");
}
}
writer.write("\nGrand Totals:\n");
writer.write("Total Execution Time: " + grandTotalTimeMillis + " ms\n");
writer.write("Total Memory Used: " + grandTotalMemoryBytes + " bytes\n");
} catch (IOException e) {
System.err.println("Error writing to results file: " + e.getMessage());
}
System.out.println("\nGrand Total Execution Time for All Sizes:"); // Display grand total execution time
System.out.println(" " + grandTotalTimeMillis + " milliseconds");
System.out.println(" " + (grandTotalTimeMillis / 1000.0) + " seconds");
System.out.println(" Grand Total Memory Used: " + grandTotalMemoryBytes + " bytes");
System.out.println("\nDetailed Results Summary:");
for (String result : detailedResults) {
System.out.println(result);
}
}
public static void mergesort2(int low, int high) { // Mergesort2 method
if (low < high) { // If low is less than high
int mid = (low + high) / 2;
mergesort2(low, mid);
mergesort2(mid + 1, high);
merge2(low, mid, high);
}
}
public static void merge2(int low, int mid, int high) {
int[] U = new int[high - low + 2]; // Temporary array for merging (1-based indexing)
totalMemoryAllocated += U.length * Integer.BYTES; // Memory allocated for temporary array
int i = low, j = mid + 1, k = 1;
// Merge the two subarrays
while (i <= mid && j <= high) {
if (S[i] <= S[j]) {
U[k++] = S[i++];
} else {
U[k++] = S[j++];
}
}
// Copy the remaining elements of the left subarray, if any
while (i <= mid) {
U[k++] = S[i++];
}
// Copy the remaining elements of the right subarray, if any
while (j <= high) {
U[k++] = S[j++];
}
// Copy the merged array back to the original array
for (k = 1; k <= (high - low + 1); k++) {
S[low + k - 1] = U[k];
}
}
public static void printArray(int[] array) {
int limit = Math.min(array.length - 1, 25); // Adjust for 1-based indexing
for (int i = 1; i <= limit; i++) {
System.out.print(array[i] + " ");
}
if (array.length > 26) {
System.out.println("... ( limited to 25 elements)");
} else {
System.out.println();
}
}
public static void printCustomArray(int[] array) {
int limit = Math.min(array.length, 25); // For 0-based indexing
for (int i = 0; i < limit; i++) {
System.out.print(array[i] + " "); // Print the array
}
if (array.length > 25) {
System.out.println("... (output limited to 25 elements)");
} else {
System.out.println();
}
}
public static int[] generateArray(String type, int size) {
int[] array = new int[size];
switch (type) {
case "Random Array":
for (int i = 0; i < size; i++) array[i] = (int) (Math.random() * 10000); // Generate random array
break;
case "Sorted Array":
for (int i = 0; i < size; i++) array[i] = i; // Generate sorted array
break;
case "Reversed Array":
for (int i = 0; i < size; i++) array[i] = size - i; // Generate reversed array
break;
case "Nearly Sorted Array":
for (int i = 0; i < size; i++) array[i] = i; // Generate nearly sorted array
for (int i = 0; i < size * 0.05; i++) array[(int) (Math.random() * size)] = (int) (Math.random() * 10000); // Randomize 5% of elements
break;
}
return array; // Return the generated array
}
}