高斯消元法解线性方程 C++代码

#include<iostream.h>
void main()
{
double a[10][10];
int n,i,j,k;
                   double sum;
cout<<"请输入未知数x的个数:";
                   cin>>n;
cout<<"请按行输入线性方程组各个系数及常数向量b:"<<endl;
for(i=1;i<=n;i++)
for(j=1;j<=n+1;j++)
cin>>a[i][j];
for(k=1;k<=n-1;k++)
{
for(i=k+1;i<=n;i++)
a[i][k]=a[i][k]/a[k][k];
    for(i=k+1;i<=n;i++)
for(j=k+1;j<=n+1;j++)
a[i][j]=a[i][j]-a[i][k]*a[k][j];
}
for(i=n;i>=1;i--)
{
sum=0.0;
for(j=i+1;j<=n;j++)
sum+=a[i][j]*a[j][n+1];
a[i][n+1]=(a[i][n+1]-sum)/a[i][i];
}
cout<<"此线性方程组的解为："<<endl;
for(i=1;i<=n;i++)