// GEM

//#include "stdafx.h"

#include <stdio.h>

#include <iostream>

#include<math.h>

#include<iomanip>

using namespace std;



float GEM(float *a[],float *b[], int N, int M)

{

	for (int i = 0; i < N; i++)

	{

		for (int j = 0; j < M; j++)

		{

			b[i][j] = a[i][j];

		}

	}



	int max = 0;

	float pom;

	for (int i = 0; i<N; i++)              //nalezení pivota

	{

		for (int j = i + 1; j<N; j++)

        {

            if (fabs(b[j][i])>fabs(b[i][i]))

                max = j;

        }



		for (int k = i; k<M; k++)

		{

			pom = b[i][k];

			b[i][k] = b[max][k];

			b[max][k] = pom;

		}



		for (int j = i + 1; j<N; j++)

        {

            for (int k = N; k >= i; k--)

            {

                b[j][k] = b[j][k] - b[i][k] * b[j][i] / b[i][i];

            }

        }

	}



    float r[N];

    int res = M-1;

    for(int i=0; i<N; i++)

       r[i]=b[i][res];

    int pr = 0;

    if(pr==0)

    {

     for(int j=N-1; j>=0; j--)

     {

       pom=0;

       for(int k=j+1; k<=N; k++)

           pom=pom+b[j][k]*r[k];

       r[j]=(b[j][N]-pom)/b[j][j];

     }



   }



  cout<<"------------------------------------------------------------------"<<endl;

   cout<<endl<<"   Reseni soustavy: "<<endl;

   for (int j = 0; j < M-1; j++)

		{

			cout<<endl<<"   x"<<j+1<<"=  "<<setprecision(2)<< r[j];   //printf("x%d = %5.3f \n",j+1, r[j]);

		}

		cout<<endl;

		cout<<"------------------------------------------------------------------"<<endl;

	return **b;

}

void vypismat(float *a[],int N,int M)

{   cout<<endl;

    for (int i = 0; i<N; i++)

	{//vypisuje prvky, když dojde na konec oadky, odoádkuje

		for (int j = 0; j<M; j++)

		{

			cout<<setw(7)<<setprecision(1) <<a[i][j];   //printf(" %5.3f ", a[i][j]);

			if (j == M - 1) cout<<endl;

			if (j == N-1) 	cout<<"  |";

		}

	}

}

void naplmatici(float *a[],int N,int M)

{

    int res; cout<<endl;

    cout<<"   Vyplnte matici: "<<endl;

	for (int x = 0; x < N; x++)

	{

		for (int j = 0; j < M; j++)

		{  cout<<"   matice["<<x<<"]["<<j<<"]= ";

					cin>>a[x][j]; //scanf("%f", &a[x][j]);



		}



	}

}

 int main()                                                

{

	int N, M;

	cout<<"   GAUSSOVA ELIMINACE "<<endl;

	cout<<"   Zadejte pocet radku matice:  ";

	 cin>>N;                   //scanf("%d", &N);

	cout<<"   Zadejte pocet sloupcu matice: ";

	 cin>>M;	                 //scanf("%d", &M);

	 cout<<endl;

	//-----------------------------------------------------------------------------

	float**pole;

	pole = new float*[N];

	for (int i = 0; i < N; i++)

	{

		pole[i] = new float[M];

	}

	naplmatici(pole,N,M);

	//-----------------------------------------------------------------------------

	float**pole1;

	pole1 = new float*[N];

	for (int i = 0; i < N; i++)

	{

		pole1[i] = new float[M];

	}

	GEM(pole, pole1, N, M);

	//------------------------------------------------------------------------------

	cout<<"   Matice soustavy rovnic:  "<<endl;

	vypismat(pole,N,M);

	cout<<"------------------------------------------------------------------"<<endl;

	cout<<"   Trojuhelnikova matice:  "<<endl;



	vypismat(pole1,N,M);



    //----------------------------------------------------------------------------------

	for (int i = 0; i<N; i++) {

		delete[] pole[i];

		delete[] pole1[i];

	}

	delete[] pole;

	delete[] pole1;



	return 0;

}