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

int Jacobi(int n,float A[][4],float B[],float X[])
{int i,j,sem;
float sum,eps=0.001,Xn[4],Xn1[4];

for(i=1;i<=n;i++)
{	sum=0;
	for(j=1;j<=n;j++)
		sum=sum+fabs(A[i][j]);
	if(sum>2*fabs(A[i][i]))
		return 1;
}
for(i=1;i<=n;i++)
Xn[i]=X[i];
do{
sem=0;
for(i=1;i<=n;i++)
	Xn1[i]=Xn[i];
for(i=1;i<=n;i++)
{	Xn[i]=B[i];
	for(j=1;j<=n;j++)
		if(j!=i)
				Xn[i]=Xn[i]-A[i][j]*Xn1[j];
	Xn[i]=Xn[i]/A[i][i];
}
for(i=1;i<=n;i++)
	if(fabs(Xn[i]-Xn1[i])>eps)
		sem=1;
}while(sem==1);
for(i=1;i<=n;i++)
	X[i]=Xn[i];
return 0;
}

int main()
{	float A[4][4]={{0,0,0,0},{0,5,0.5,3},{0,-0.9,2,-1},{0,2.1,0.6,3}};
	float B[4]={0,3,2,1},X[4];
	int n=3,i;
	if(Jacobi(n,A,B,X)==1)
		cout<<"Eroare!"<<endl;
	else
		for(i=1;i<=n;i++)
			cout<<X[i]<<endl;
system("pause");
return 0;
}