Cod sursa(job #952652)

Utilizator primulDarie Sergiu primul Data 23 mai 2013 19:20:38
Problema Algoritmul lui Gauss Scor 100
Compilator cpp Status done
Runda Arhiva educationala Marime 1.26 kb
#include<fstream>
#include<iomanip>
#define eps 0.0000001
using namespace std;
ifstream f("gauss.in");
ofstream g("gauss.out");
int i,j,n,m,k,p;
double x[305],a[305][305];
int main()
{
    f>>n>>m;
    for(i=1;i<=n;++i)
    for(j=1;j<=m+1;++j)
    f>>a[i][j];
    for(i=1,j=1;i<=n&&j<=m;)
    {
        for(k=i;k<=n;++k)
        if(a[k][j]<-eps||a[k][j]>eps)
        {
            break;
        }
        if(k>n)
        {
            ++j;
            continue;
        }
        if(k!=i)
        {
            for(p=1;p<=m+1;++p)
            swap(a[i][p],a[k][p]);
        }
        for(p=j+1;p<=m+1;++p)
        a[i][p]=a[i][p]/a[i][j];
        a[i][j]=1;
        for(k=i+1;k<=n;++k)
        {
            for(p=j+1;p<=m+1;++p)
            {
                a[k][p]-=(a[k][j]*a[i][p]);
            }
            a[k][j]=0;
        }
        ++i;
        ++j;
    }
    for(i=n;i;--i)
    for(j=1;j<=m+1;++j)
    if(a[i][j]>eps||a[i][j]<-eps)
    {
        if(j==m+1)
        {
            g<<"Imposibil\n";
            return 0;
        }
        x[j]=a[i][m+1];
        for(k=j+1;k<=m;++k)
        x[j]-=(x[k]*a[i][k]);
        break;
    }
    for(i=1;i<=m;++i)
    g<<fixed<<setprecision(8)<<x[i]<<' ';
    return 0;
}