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#include <iostream>
#include <string>
#include <sstream>
#include <fstream>

/*
input.txt 的內容如下
2 2 -1 0 1
-1 -1 2 -3 1
1 1 -2 0 -1
0 0 1 1 1
*/

using namespace std;

int main(int argc, char *argv[])
{   
    int Row = 0, Column = 0, LeadOne=0;
    string GetNum;
    fstream InPut, OutPut;
    double **M = new double*[200], temp;
    for (int i=0;i<200;i++)
        M[i] = new double[200];
        
    InPut.open ("input.txt", ios::in);
    OutPut.open ("output.txt", ios::out);
    if (!InPut)
       cerr << "Failed to open file！";
    else
    {
       while (!InPut.eof())
       {
             getline(InPut, GetNum);
             stringstream TransNum(GetNum, istringstream::in);
             while (!TransNum.eof())
             {                     
                   TransNum >> M[Row][Column];
                   Column++;
             }
             Row++;
             if (!InPut.eof())
                Column=0;
       }
    } 
    
    for (int r=0; r<Row; r++)
    {
        int i = r, LeadTemp = LeadOne;
        while (M[i][LeadTemp] == 0)
        {
              i++;
              if (i == Row)
              {
                 i = r;
                 LeadTemp++;
                 if (LeadTemp == Column)
                    break;
              }
              for (int c=0; c<Column; c++)
              {
                  temp = M[i][c];
                  M[i][c] = M[r][c];
                  M[r][c] = temp;    
              }      
        }
        
        if (M[r][LeadOne] != 0 && LeadOne != Column-1)
        {
           temp = M[r][LeadOne];
           for (int m=0; m<Column; m++)
               M[r][m] = M[r][m]/temp;
        }
        
        for (int j=0; j<Row; j++)
        {
            if (j!=r)
            {
               temp = M[j][LeadOne];
               for (int p=0; p<Column; p++)
                   M[j][p] -= temp*M[r][p];
            }
        }
        LeadOne++;
    }
        
    for (int x=0; x<Row; x++)
    {
        for (int y=0; y<Column; y++)
            OutPut << M[x][y] << " ";     
        OutPut << '\n';
    }

    for (int i=0; i<200; i++)
        delete [] M[i];
    delete [] M;
    InPut.close();
    OutPut.close(); 
    return EXIT_SUCCESS;
}