HDU 1874 最短路径

来源：互联网发布：windows资源管理器在哪编辑：程序博客网时间：2024/06/05 08:41

有重边，wa了半天。

#include <iostream>using namespace std;#define N 205int n, m;int map[N][N];int sea[N];int D[N];int flag[N];void floyd(){for(int i = 0; i < n; i++)for(int j = 0; j < n; j++)for(int k = 0; k < n; k++){if(map[j][i] + map[i][k] < map[j][k])map[j][k] = map[j][i] + map[i][k];}}void dijkstra(){ for(int i = 0; i < n; i++)D[i] = map[0][i];for(int cnt = 0; cnt < n-1; cnt++){int min = 0x7fffffff;int index = -1;for(int i = 0; i < n; i++){if(D[i] < min && flag[i] == 0){index = i;min = D[i];}}flag[index] = 1;for(int i = 0; i < n; i++){if(flag[i])continue;for(int j = 0; j < n; j++){if(flag[j] == 0)continue;if(D[j] + map[j][i] < D[i])D[i] = D[j] + map[j][i];}}}}int main(){while(~scanf("%d %d", &n, &m)){for(int i = 0; i < N; i++)for(int j = 0; j < N; j++)map[i][j] = 0x1fffffff;for(int i = 0; i < n; i++)map[i][i] = 0;ni yint x, y, t;for(int i = 0; i < m; i++){scanf("%d %d %d", &x, &y, &t);if(t < map[x][y]) //真恶心，重边map[x][y] = map[y][x] = t;}floyd();scanf("%d %d", &x, &y);if(map[x][y] < 0x1fffffff)cout << map[x][y] << endl;elsecout << "-1" << endl;}return 0;}