Form a new number by doubling each digit Dry Run in C

Form a new number by doubling each digit is an interactive C dry run visualizer from the For 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.

Form a new number by doubling each digit Program Code

#include <stdio.h>
int main() {
    int num, result = 0, place = 1, temp;
    printf("Enter a number: ");
    scanf("%d", &num);
    
    for(temp = num; temp != 0; temp /= 10) {
        int digit = temp % 10;
        int doubled = digit * 2;
        
        // Handle doubled value which can be 0-18
        if(doubled >= 10) {
            // Two-digit result: add both digits
            int firstDigit = doubled / 10;
            int secondDigit = doubled % 10;
            result = secondDigit * place + result;
            place *= 10;
            result = firstDigit * place + result;
            place *= 10;
        } else {
            result = doubled * place + result;
            place *= 10;
        }
    }
    
    printf("After doubling each digit: %d\n", result);
    return 0;
}

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