#include <iostream>
#include<stdlib.h>
#include<math.h>
using namespace std;

float Gauss(int n, float A[][4], float B[],float X[])
{
int i,k,j;
float m,d;
for(i=1;i<=n-1;i++)
for(k=i+1;k<=n;k++)
{
m=A[k][i]/A[i][i];
for(j=i;j<=n;j++)
A[k][j]=A[k][j]-m*A[i][j];
B[k]=B[k]-m*B[i];
}
d=1;
if(A[n][n]==0)
return 1;
for(i=1;i<=n;i++)
d=d*A[i][i];
for(i=n;i>=1;i--)
{
X[i]=B[i];
for(j=n;j>=i+1;j--)
X[i]=X[i]-A[i][j]*X[j];
X[i]=X[i]/A[i][i];
}
return d;
}

int main()
{
float A[4][4]={{0,0,0,0},{0,3,1,-0.7},{0,1,3,-0.5},{0,0.8,0.7,2}};
float B[4]={0,1,3,2}, X[3];
int n=3,i;
cout<<"Determinantul sistemului este "<<Gauss(n,A,B,X)<<endl;
for(i=1;i<=n;i++)
cout<<X[i]<<endl;
return 0;
}