Floyd(弗洛伊德) —— 多源最短路

在Floyd算法中,我们需要通过每一个点对两个点进行连接,以此求出两点之间的最短路,因此,我们要遍历每一个点

#include<iostream>
#include<cstdio>
#include<cstring>
using namespace std;

const int MAXN = 1005;
const int INF = 0x3f3f3f3f;

int MAP[MAXN][MAXN];
int n, m;

void Floyd()
{
	for(int k = 1; k <= n; k++)
		for(int i = 1; i <= n; i++)
			for(int j = 1; j <= n; j++)
				if(MAP[i][j] > MAP[i][k] + MAP[k][j])
					MAP[i][j] = MAP[i][k] + MAP[k][j];
}

int main()
{
	while(~scanf("%d%d", &n, &m))
	{
		for(int i = 1; i <= n; i++)
			for(int j = 1; j <= n; j++)
				if(i == j) MAP[i][j] = 0;
				else MAP[i][j] = INF;
		int a, b, c;
		for(int i = 1; i <= m; i++)
		{
			scanf("%d%d%d", &a, &b, &c);
			MAP[a][b] = MAP[b][a] = c;
		}
		Floyd();
		for(int i = 1; i <= n; i++)
		{
			for(int j = 1; j <= n; j++)
			{
				printf("%d ", MAP[i][j]);
			}
			printf("\n");
		}
	}
	return 0;
}

某些细节可以是适当更改

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转载自blog.csdn.net/someone_and_anyone/article/details/80964790