Example: Prime and Composite Numbers C Program using For loop

C
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// Prime and Composite Numbers C Program using For loop
#include <stdio.h>

int main() {
    int x, i, f = 0;
    // x - Value of the input integer number

    printf("-----Enter the positive integer number-----\n");
    scanf("%d", &x);

    if (x == 1) {
        printf("1 is neither the prime nor the composite number!\n");
    } else {

        for (i = 2; i <= x / 2; ++i) {
            // This is the condition for non-prime
            if (x % i == 0) {
                f = 1;
                break;
            }
        }

        if (f == 0) {
            printf("\n%d is the prime number.\n", x);
        } else {
            printf("\n%d is not the prime number.\n", x);
        }
    }
    return 0;
}