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
", 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
", G[1][n]);
    return 0;
}
/*
4
-1 1 -1 -1
-1 -1 1 -1
-1 -1 -1 1
-1 -1 -1 -1
*/