Digital Root (Repeat sum until single digit) Dry Run in C

Digital Root (Repeat sum until single digit) is an interactive C dry run visualizer from the Recursion 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.

Digital Root (Repeat sum until single digit) Program Code

#include <stdio.h>

int sumOfDigits(int n) {
    if(n < 10) {
        return n;
    }

    int lastDigit = n % 10;
    int remainingSum = sumOfDigits(n / 10);
    int sum = lastDigit + remainingSum;
    return sum;
}

int digitalRoot(int n) {
    int singleSum = sumOfDigits(n);
    if(singleSum < 10) {
        return singleSum;
    }
    return digitalRoot(singleSum);
}

int main() {
    int num = 9875;
    int root = digitalRoot(num);
    printf("Number: %d\n", num);
    printf("Digital Root: %d\n", root);
    return 0;
}

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