Sum of Both Diagonals (Without Double Counting Center) Dry Run in C

Sum of Both Diagonals (Without Double Counting Center) is an interactive C dry run visualizer from the Two D 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.

Sum of Both Diagonals (Without Double Counting Center) Program Code

#include <stdio.h>
int main() {
    int matrix[3][3] = {{1, 2, 3}, {4, 5, 6}, {7, 8, 9}}, i;
    int sum = 0;
    
    for(i = 0; i < 3; i++) {
        // Add main diagonal
        sum += matrix[i][i];
        // Add secondary diagonal
        sum += matrix[i][2 - i];
    }
    // Subtract center if matrix size is odd (counted twice)
    sum -= matrix[1][1];
    
    printf("Sum of both diagonals = %d\n", sum);
    return 0;
}

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