Creating a matrix that has its elements as the sum of the indices of that element-CodePudding

int main() {
    int n = 0;
    int matrix[n][n];

    printf("Insert the order of the matrix:");
    scanf("%d", &n);
    for (int i = 0; i < n; i  )
        for (int j = 0; j < n; j  )
            matrix[i][j] = i   j;

    printf("The matrix is:\n");
    for (int i = 0; i < n; i  ) {
        for (int j = 0; j < n; j  ) {
            printf("%d ", matrix[i][j]);
        }
    }

for a 2x2 matrix the output should be 0 1 1 2, but it is 1 2 1 2, and for a 3x3 matrix it should be 0 1 2 1 2 3 2 3 4 but it shows 2 3 4 2 3 4 2 3 4

The issue is that my output is always just my first row of the matrix, repeated n times. Any help?

CodePudding user response：

#include <stdio.h>

int main() {
    int n = 0;
    printf("Insert the order of the matrix:");
    scanf("%d", &n);
    int matrix[n][n];
    for (int i = 0; i < n; i  )
        for (int j = 0; j < n; j  )
            matrix[i][j] = i   j;

    printf("The matrix is:\n");
    for (int i = 0; i < n; i  ) {
        for (int j = 0; j < n; j  ) {
            printf("%d ", matrix[i][j]);
        }
    }
}

CodePudding user response：

You declare the array with size n equal zero. Then the length of a row is zero, hence the offset for each consecutive row is zero, too. That means all rows are stored at the same place. As a final result, the last row's values overwrite all the previous rows.

Do input n before declaring matrix[n][n].