C program to find transpose of a matrix

Transpose of a matrix is obtained by changing rows to columns and columns to rows. In other words, transpose of A[][] is obtained by changing A[i][j] to A[j][i].

Recommended: Please solve it on “PRACTICE ” first, before moving on to the solution.

The below C program finds transpose of A[][] and stores the result in B[][], we can change N for different dimension.

```#include <stdio.h>
#define N 4

// This function stores transpose of A[][] in B[][]
void transpose(int A[][N], int B[][N])
{
int i, j;
for (i = 0; i < N; i++)
for (j = 0; j < N; j++)
B[i][j] = A[j][i];
}

int main()
{
int A[N][N] = { {1, 1, 1, 1},
{2, 2, 2, 2},
{3, 3, 3, 3},
{4, 4, 4, 4}};

int B[N][N], i, j;

transpose(A, B);

printf("Result matrix is \n");
for (i = 0; i < N; i++)
{
for (j = 0; j < N; j++)
printf("%d ", B[i][j]);
printf("\n");
}

return 0;
}
```

Output:

```Result matrix is
1 2 3 4
1 2 3 4
1 2 3 4
1 2 3 4```

The program can be extended for rectangular matrices. The following post can be useful for extending this program.

How to pass a 2D array as a parameter in C?

The time complexity of the above program is O(n2).