C Exercises: Check a given array of integers of length 3 and create a new array

Last update on July 28 2025 12:50:03 (UTC/GMT +8 hours)

44. Modify Array: 5 Followed by 7 to 5 and 1

Write a C program to check a given array of integers of length 3 and create a new array. If there is a 5 in the given array immediately followed by a 7 then set 7 to 1.

C Code:

#include <stdio.h>
#include <stdlib.h>

// Function prototype for 'print_array'
void print_array(int parray[], int size);

int main(void){
    // Declaration and initialization of variables
    int arr_size;
    int array1[] = {1, 5, 7};

    // Calculating the size of the array
    arr_size = sizeof(array1)/sizeof(array1[0]);

    // Printing elements in the original array
    printf("Elements in original array are: ");  
    print_array(array1, arr_size);   

    // Loop through the array to check for specific condition and modify elements
    for (int i = 0; i < arr_size - 1; i++)
    {
        if (array1[i] == 5 && array1[i + 1] == 7)
            array1[i + 1] = 1;
    }

    // Printing elements in the modified array
    printf("Elements in new array are: ");  
    print_array(array1, arr_size);        
} 

// Definition of the 'print_array' function
void print_array(int parray[], int size)
{
   int i;      
   for( i=0; i<size-1; i++)  
    {  
        // Printing each element with a comma and a space
        printf("%d, ", parray[i]);  
    } 
    // Printing the last element without a comma and space
    printf("%d ", parray[i]);  
    // Printing a new line to separate the elements
    printf("\n");   
}

Sample Output:

Elements in original array are: 1, 5, 7 
Elements in new array are: 1, 5, 1

Pictorial Presentation:

C Programming Algorithm: check a given array of integers of length 3 and create a new array

Flowchart:

For more Practice: Solve these Related Problems:

Write a C program to change every occurrence of 7 preceded by 3 to 0 in an array of length 3.
Write a C program to replace the number following 4 with 9 in a 3-element array.
Write a C program to modify a 3-element array so that if a 6 is immediately followed by an 8, replace 8 with 2.
Write a C program to check a 3-element array and if the sequence 2, 4 appears, replace 4 with 0.

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