EX-21-POINTERS
Write a C program to convert a 23.65 into 25 using pointer
- Declare a double variable to hold the floating-point number (23.65).
- Declare a pointer to double to point to the address of the variable.
- Use the pointer to modify the value to 25.0.
- Print the modified value.
#include <stdio.h>
int main()
{
double num = 23.65;
double *ptr;
ptr = #
*ptr = 25.0;
printf("Modified value: %.1lf\n", num);
return 0;
}
Thus the program to convert a 23.65 into 25 using pointer has been executed successfully.
Write a C program to calculate the Product of first 12 natural numbers using Recursion
- Define a recursive function calculateProduct that takes an integer parameter n.
- Return n multiplied by the result of the calculateProduct function called with n - 1.
- Declare an integer variable n and an unsigned long long variable product.
- Initialize n with the value 12 (for the first 12 natural numbers).
- Call the calculateProduct function with n and store the result in the product variable.
- Print the result, indicating it is the product of the first 12 natural numbers.
#include <stdio.h>
unsigned long long calculateProduct(int n)
{
if (n == 1)
return 1;
else
return n * calculateProduct(n - 1);
}
int main()
{
int n = 12;
unsigned long long product;
product = calculateProduct(n);
printf("The product of the first %d natural numbers is: %llu\n", n, product);
return 0;
}
Thus the program has been executed successfully.
Write C Program to find Sum of each row of a Matrix
- Declare and initialize the matrix with the desired values.
- Create a loop to iterate through each row of the matrix.
- Inside the loop, calculate the sum of the elements in each row.
- Print the sum for each row.
#include <stdio.h>
int main()
{
int i, j;
int matrix[3][3] = {
{1, 2, 3},
{4, 5, 6},
{7, 8, 9}
};
int rows = 3, cols = 3;
for (i = 0; i < rows; i++)
{
int sum = 0;
for (j = 0; j < cols; j++)
{
sum += matrix[i][j];
}
printf("Sum of row %d = %d\n", i + 1, sum);
}
return 0;
}
Write C program for the below pyramid string pattern. Enter a string: PROGRAM Enter number of rows: 5 P R O G R A M P R O G R A M P R O G R A M
- Input the number of rows for the pyramid (e.g., num_rows).
- Initialize variables:i for the row count (starting from 1),j for the character count (starting from 1)
- Start a loop for i from 1 to num_rows (for each row of the pyramid).
- Calculate the midpoint position as midpoint = (2 * num_rows - 1) / 2.
- End the program.
#include <stdio.h>
#include <string.h>
int main()
{
char str[100];
int num_rows, i, j;
printf("Enter a string: ");
scanf("%s", str);
printf("Enter number of rows: ");
scanf("%d", &num_rows);
int midpoint = (2 * num_rows - 1) / 2;
for (i = 1; i <= num_rows; i++)
{
for (midpoint = 1; midpoint <= num_rows - i; midpoint++)
printf(" ");
for (j = 1; j <= i; j++)
printf("%s ", str);
printf("\n");
}
return 0;
}
Thus the C program to String process executed successfully
.
Write a c program to read and display an array of any 6 integer elements using pointer
Step 1: Start the program. Step 2: Declare the following: • Integer variable i for iteration. • Integer variable n to store the number of elements. • Integer array arr[10] to hold up to 10 elements. • Integer pointer parr and initialize it to point to the array arr. Step 3: Read the value of n (number of elements) from the user. Step 4: Loop from i = 0 to i < n: • Read an integer value and store it in the address parr + i using pointer arithmetic. Step 5: Loop from i = 0 to i < n: • Print the element at *(parr + i) using pointer dereferencing. Step 6: End the program.
#include <stdio.h>
int main()
{
int arr[10];
int n, i;
int *parr;
parr = arr;
printf("Enter number of elements (max 6): ");
scanf("%d", &n);
printf("Enter %d integer elements:\n", n);
for (i = 0; i < n; i++)
{
scanf("%d", (parr + i));
}
printf("\nArray elements are:\n");
for (i = 0; i < n; i++)
{
printf("%d ", *(parr + i));
}
printf("\n");
return 0;
}
Thus the C program to read and display an array of any 6 integer elements using pointer has been executed




