Easy csharp

Sum of diagonal elements

Problem

Sum main diagonal of square matrix {{1,2,3},{4,5,6},{7,8,9}} (1+5+9=15).

Hints

Add m[i,i] for all i.

Your practice code

Ready — edit the code above and click Run.

Solution

using System;

class Program
{
    static void Main()
    {
        int[,] m = { {1,2,3}, {4,5,6}, {7,8,9} };
        int sum = 0;
        for (int i = 0; i < m.GetLength(0); i++)
            sum += m[i, i];
        Console.WriteLine(sum);
    }
}

Try solving on your own first, then reveal the official answer.

Explanation

Main diagonal: indices where row equals column.

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