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Subtraction of two matrices

Given two matrices, we will write a function that subtracts the given matrices.

Example

INPUT
A[4][4] = { {1, 4, 7, 9},
{1, 6, 7, 6},
{6, 3, 7, 12},
{4, 4, 4, 4}};

B[4][4] = { {1, 1, 1, 1},
{2, 2, 2, 2},
{3, 3, 3, 3},
{4, 9, 1, 7}};

We will subtract matrix B from matrix A

OUTPUT
{{0 3 6 8},
{-1 4 5 4},
{3 0 4 9},
{0 -5 3 -3}}

Time Complexity: O(n^2),

where n is the size of the matrix

Algorithm

1. For each row in the two matrices
a. Subtract the respective elements in matrix B with the elements in matrix A and store the     result in the same position in some auxilary matrix
b. move to the next row
2. Print the auxilary matrix

C++ Program

```#include <bits/stdc++.h>
using namespace std;
#define N 4
int main()
{
int A[N][N] = { {1, 4, 7, 9},
{1, 6, 7, 6},
{6, 3, 7, 12},
{4, 4, 4, 4}};

int B[N][N] = { {1, 1, 1, 1},
{2, 2, 2, 2},
{3, 3, 3, 3},
{4, 9, 1, 7}};

for(int i=0; i <N; i++)
{
for(int j=0; j<N; j++)
{
A[i][j] = A[i][j] - B[i][j];
cout<<A[i][j]<<" ";
}
cout<<endl;
}

return 0;
}```