Floyd 算法 打印路径模板

#include <iostream>

#include <cstdlib>

#include <cstdio>

#include <algorithm>

#include <vector>

#include <queue>

#include <cmath>

#include <cstring>

using namespace std;

#define INF 0xfffffff

#define maxn 40



int G[maxn][maxn], Path[maxn][maxn], n;



void Floyd()

{

    for(int k=1; k<=n; k++)

    {

        for(int i=1; i<=n; i++)

        {

            for(int j=1; j<=n; j++)

            {

                if(G[i][j] > G[i][k] + G[k][j])

                {

                    G[i][j] = G[i][k] + G[k][j];

                    Path[i][j] = Path[i][k];

                }

            }

        }

    }

}

void PutPath(int Star,int End)

{

    while(Star != End)

    {

        printf("%d---->", Star);

        Star = Path[Star][End];

    }

    printf("%d\n", End);

}

void Init()

{

    for(int i=1; i<=n; i++)

    {

        for(int j=1; j<=n; j++)

        {

            Path[i][j] = j;

        }

    }

}



int main()

{



    cin >> n;



    Init();



    for(int i=1; i<=n; i++)

    {

        for(int j=1; j<=n; j++)

        {

            cin >> G[i][j];

            if(G[i][j] == -1)

                G[i][j] = INF;

        }

    }

    Floyd();





    PutPath(1,n);



    printf("%d\n", G[1][n]);

    return 0;

}

/*

4

-1 1 -1 -1

-1 -1 1 -1

-1 -1 -1 1

-1 -1 -1 -1

*/