Check whether each number is prime or composite (for loop) Dry Run in C

Check whether each number is prime or composite (for loop) is an interactive C dry run visualizer from the Nested programs section. Study the source code, then use the execution controls to follow each step, variable update, highlighted line, and console output.

This page provides a browser-based dry run with source-code highlighting, auto-scroll, voice narration controls, and execution output for learning the program step by step.

Check whether each number is prime or composite (for loop) Program Code

#include <stdio.h>
int main() {
    int start, end, num, i;
    printf("Enter range (start end): ");
    scanf("%d %d", &start, &end);
    
    printf("Number\tClassification\n");
    for(num = start; num <= end; num++) {
        if(num < 2) {
            printf("%d\tNeither prime nor composite\n", num);
            continue;
        }
        
        int isPrime = 1;
        for(i = 2; i * i <= num; i++) {
            if(num % i == 0) {
                isPrime = 0;
                break;
            }
        }
        
        if(isPrime)
            printf("%d\tPrime\n", num);
        else
            printf("%d\tComposite\n", num);
    }
    return 0;
}

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