C PROGRAMMING PROGRAM • MATRICES

Calculate Every Matrix Row and Column Sum

Learn how to calculate every matrix row and column sum using a clear C program.

Intermediate2D arraysNested loopsMatrices

PROBLEM UNDERSTANDING

Input and expected output

Sample input

2 3
1 2 3
4 5 6

Sample output

Row 1 sum = 6
Row 2 sum = 15
Column 1 sum = 5
Column 2 sum = 7
Column 3 sum = 9

COMPLETE C PROGRAM

Complete C implementation

#include <stdio.h>

int main(void)
{
    int rows, columns, matrix[10][10];

    scanf("%d %d", &rows, &columns);
    if (rows < 1 || rows > 10 || columns < 1 || columns > 10) return 1;
    for (int row = 0; row < rows; row++)
        for (int column = 0; column < columns; column++) scanf("%d", &matrix[row][column]);
    for (int row = 0; row < rows; row++) {
        int sum = 0;
        for (int column = 0; column < columns; column++) sum += matrix[row][column];
        printf("Row %d sum = %d\n", row + 1, sum);
    }
    for (int column = 0; column < columns; column++) {
        int sum = 0;
        for (int row = 0; row < rows; row++) sum += matrix[row][column];
        printf("Column %d sum = %d\n", column + 1, sum);
    }
    return 0;
}

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EXPECTED OUTPUT FOR THE SAMPLE

Row 1 sum = 6
Row 2 sum = 15
Column 1 sum = 5
Column 2 sum = 7
Column 3 sum = 9

0%Step 0 of 0

PROGRAM EXPLANATION

Algorithm and explanation

Read the required input values.
Traverse by rows for row sums and by columns for column sums.
Display the computed result.

Traverse by rows for row sums and by columns for column sums.

EFFICIENCY

Time and space complexity

Time complexity

O(rows × columns)

Auxiliary space

O(rows × columns)

DEBUGGING CHECKLIST

Common mistakes

Check this

Use the correct format specifier for every variable.

Check this

Initialize variables before using their values.

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Check braces, semicolons and input order carefully.

Try it yourself

Practice: Run the program with the sample input, predict its output, and then test one boundary case of your own.