Find strong numbers in a range (for loop) Dry Run in C

Find strong numbers in a range (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.

Find strong numbers in a range (for loop) Program Code

#include <stdio.h>
int factorial(int n) {
    int fact = 1, i;
    for(i = 1; i <= n; i++) {
        fact *= i;
    }
    return fact;
}

int main() {
    int start, end, num;
    printf("Enter range (start end): ");
    scanf("%d %d", &start, &end);
    
    printf("Strong numbers between %d and %d:\n", start, end);
    int found = 0;
    
    for(num = start; num <= end; num++) {
        int original = num, sum = 0, temp = num;
        
        while(temp != 0) {
            int digit = temp % 10;
            sum += factorial(digit);
            temp /= 10;
        }
        
        if(sum == original) {
            printf("%d ", original);
            found++;
        }
    }
    
    if(found == 0) printf("None found");
    printf("\nTotal strong numbers: %d\n", found);
    return 0;
}

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