Gauss Jordan Method C++

#include<iostream>
#include<iomanip>
#include<cmath>

using namespace std;
#define N 4

int main()
{
float a[N][N+1],t;
int i,j,k;
cout<<"Enter the elements of the";
cout<<" augmented matrix rowwise"<<endl;

for(i=0;i<N;i++)
for(j=0;j<N+1;j++)
cin>>a[i][j];

cout<<fixed;
for(j=0;j<N;j++)
for(i=0;i<N;i++)
if(i!=j)
{
t=a[i][j]/a[j][j];
for(k=0;k<N+1;k++)
a[i][k] -= a[j][k]*t;
}
//printing the diagonal matrix

cout<<"The diagonal matrix is :-"<<endl;
for(i=0;i<N;i++)
{
for(j=0;j<N+1;j++)
cout<<setw(9)<<setprecision(4)<<a[i][j];
cout<<endl;
}
//Now printing the results
cout<<"The solution is:-"<<endl;
for(i=0;i<N;i++)
{cout<<"x["<<setw(3)<<i+1<<"]=";
cout<<setw(7)<<setprecision(4);
cout<<a[i][N]/a[i][i]<<endl;
}
return 0;
}