hdu-2544-最短路(dijkstra算法模板)

 题目链接

题意很清晰，入门级题目，适合各种模板，可用dijkstra, floyd, Bellman-ford, spfa

Dijkstra链接

Floyd链接

Bellman-Ford链接

SPFA链接

/*
    Name:HDU-2544-最短路
    Copyright:
    Author:
    Date: 2018/4/17 10:34:47
    Description:
    dijkstra模板 
*/
#include <cstring>
#include <cstdio>
#include <iostream>
using namespace std; 
const int MAXN = 105;
const int INF = 0x3f3f3f3f;
int dis[MAXN], g[MAXN][MAXN], N, M;
bool v[MAXN];
void dijkstra() {
    for (int i=1; i<=N; i++) {
        dis[i] = INF;
    }
    dis[1] = 0;
    memset(v, 0, sizeof(v));
    for (int i=1; i<=N; ++i)  {
        int mark=-1, mindis=INF;
        for (int j=1; j<=N; j++) {
            if (!v[j] &&dis[j] <mindis) {
                mindis = dis[j];
                mark = j;
            }
        }
        v[mark] = 1;
        for (int j=1; j<=N; j++) {
            if (!v[j]) {
                dis[j] = min(dis[j], dis[mark] + g[mark][j]);
            }
        }
    }
}
int main()
{
//    freopen("in.txt", "r", stdin);
    while (~scanf("%d %d", &N, &M) && (N+M)) {
        memset(g, 0x3f, sizeof(g));
        for (int i=0; i<M; i++) {
            int a, b, c;
            scanf("%d %d %d", &a, &b, &c);
            if (g[a][b] > c) {
                g[a][b] = g[b][a] = c;
            }
        }
        dijkstra();
        cout<<dis[N]<<endl;
    }
    return 0;
}