Selection sort

BinarySearch.c

@@ -0,0 +1,29 @@
+#include<stdio.h>
+
+int search(int lo,int hi,int arr[],int x){
+	if(lo > hi)
+		return 0;
+
+	int mid = (lo+hi)/2;
+	if(arr[mid] == x)
+		return 1;
+	if(arr[mid] > x)
+		return search(lo,mid-1,arr,x);
+	else 
+		return search(mid+1,hi,arr,x);
+}
+int main(){
+	int n,arr[100010],x,i;
+
+	scanf("%d",&n);
+	for(i=0;i<n;i++)
+		scanf("%d",&arr[i]);
+	scanf("%d",&x);
+
+	if(search(0,n-1,arr,x))
+		printf("Number present.");
+	else 
+		printf("Number not present");
+
+	return 0;
+}

SelectionSort.c

@@ -0,0 +1,40 @@
+#include <stdio.h>
+
+void swap(int *xp, int *yp){
+    int temp = *xp;
+    *xp = *yp;
+    *yp = temp;
+}
+
+void selectionSort(int arr[], int n){
+    int i, j, min_idx;
+
+    for (i = 0; i < n-1; i++){
+        min_idx = i;
+        for (j = i+1; j < n; j++)
+          if (arr[j] < arr[min_idx])
+            min_idx = j;
+
+        swap(&arr[min_idx], &arr[i]);
+    }
+}
+
+void printArray(int arr[], int size){
+    int i;
+    for (i=0; i < size; i++)
+        printf("%d ", arr[i]);
+    printf("\n");
+}
+
+int main(){
+	int n,arr[100010],i;
+
+    scanf("%d",&n);
+    for(i=0;i<n;i++)
+    	scanf("%d",&arr[i]);
+
+    selectionSort(arr, n);
+    printf("Sorted array: \n");
+    printArray(arr, n);
+    return 0;
+}

merge.c

@@ -0,0 +1,58 @@
+#include<stdio.h>
+
+int a[1000000];
+
+void merge(int low, int mid, int high){
+	int n1=mid-low+1;
+	int n2=high-mid;
+	int i,j,k;
+	int left[1000000],right[1000000];
+
+	for(i=0;i<n1;i++)
+		left[i]=a[low+i];
+	for(i=0;i<n2;i++)
+		right[i]=a[mid+1+i];
+	i=0,j=0,k=low;
+	while(i<n1 && j<n2){
+		if(left[i]<=right[j]){
+			a[k++]=left[i++];
+		}
+		else{
+			a[k++]=right[j++];
+		}
+	}
+	while(i<n1)
+		a[k++]=left[i++];
+	while(j<n2)
+		a[k++]=right[j++];
+}
+
+void sort(int low, int high){
+	int mid;
+	//mid = (low+high)/2;
+	if(low<high){
+		mid = (low+high)/2;
+		sort(low,mid);
+		sort(mid+1,high);
+		merge(low,mid,high);
+	}
+}
+
+int main(){
+	int n,len;
+	int i=0;
+	while(scanf("%d",&n)!=EOF){
+		a[i++]=n;
+	}
+	len=i;
+	//printf("%d\n",i);
+	//for(i=0;i<len;i++)
+	//	printf("%d ", a[i]);
+	//printf("\n");
+	sort(0,len-1);
+	for(i=0;i<len;i++){
+		printf("%d ",a[i]);
+	}
+	printf("\n");
+	return 0;
+}

prime checker.c

@@ -0,0 +1,25 @@
+#include<stdio.h>
+#include<math.h>
+
+int main(){
+	int num;
+
+	scanf("%d",&num);
+
+	int isPrime = 1;
+
+	int i;
+	for(i=2;i<=sqrt(num);i++){
+		if(num%i == 0){
+			isPrime = 0;
+			break;
+		}
+	}
+	if(isPrime && num > 1){
+		printf("The number is a prime.");
+	} else{
+		printf("The number is not a prime.");
+	}
+
+	return 0;
+}