标签：最短路

最短路

2 1
1 2 3
3 3
1 2 5
2 3 5
3 1 2
0 0

3
2

#include <stdio.h>
#include <string.h>
#define M 105
#define INF 0x3f3f3f3f

int map[M][M], dis[M], n, m;
bool vis[M];

int min(int a, int b){
    return a<b?a:b;
}

void floyd(){
    int i, j, k;
    for(k = 1; k <= n; k ++)
    for(i = 1; i <= n; i ++)
        for(j = 1; j <= n; j ++)
            map[i][j] = min(map[i][j], map[i][k]+map[k][j]);
        
}

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

#include <stdio.h>
#include <string.h>
#include <queue>
#define M 105
#define INF 0x3f3f3f3f
using std::queue;

int map[M][M], dis[M], n, m;
bool vis[M];

int min(int a, int b){
    return a<b?a:b;
}

void spfa(){
    int i, j, pos;
    for(i = 1; i <= n; i++){
        dis[i] = INF;
        vis[i] = 0;
    }
    dis[1] = 0;
    vis[1] = 1;
    queue<int >q;
    q.push(1);
    while(!q.empty()){
        int temp = q.front();
        q.pop();
        vis[temp] = 0;
        for(i = 1; i <= n; i ++){
            if(dis[i] > dis[temp]+map[temp][i]){
                dis[i] = dis[temp]+map[temp][i];
                if(!vis[i]){
                    vis[i] = 1;
                    q.push(i);
                }
            }
        }
    }
}
int main(){
    while(scanf("%d%d", &n, &m), n||m){
        int i, j, a, b, c;
        for(i = 0; i <= n; i ++)
            for(j = 0; j <= n; j ++)
                map[i][j] = INF;
        for(i = 0; i < m; i ++){
            scanf("%d%d%d", &a, &b, &c);
            if(map[a][b] > c){
                map[a][b] = map[b][a] = c;
            }
        }
        spfa();
        printf("%d\n", dis[n]);
    }
    return 0;
}

#include <stdio.h>
#include <string.h>
#define M 105
#define INF 0x3f3f3f3f

int map[M][M], low[M], n, m;
bool vis[M];

int dijstra(){
    int ans = 0, pos, min, i, j;
    for(i = 1; i <= n; i ++){
        low[i] = map[1][i];
        vis[i] = 0;
    }
    vis[1] = 0;
    pos = 1;
    for(i = 1; i < n; i ++){
        min = INF;
        for(j = 1; j <= n; j ++){
            if(!vis[j]&&low[j]<min){
                min = low[j]; pos = j;
            }
        }
        ans += min; vis[pos] = 1;
        for(j = 1; j <= n; j ++){
            if(!vis[j]&&low[j] > low[pos]+map[pos][j])
                low[j] = low[pos]+map[pos][j];
        }
    }
    return low[n];
}

int main(){
    while(scanf("%d%d", &n, &m), n||m){
        int i, j, a, b, c;
        for(i = 0; i <= n; i ++){
            for(j = 0; j <= n; j ++)
            map[i][j] = INF;
        }
        for(i = 0; i < m; i ++){
            scanf("%d%d%d", &a, &b, &c);
            if(map[a][b] > c){
                map[a][b] = map[b][a] = c;
            }
        }
        printf("%d\n", dijstra());
    }
    return 0;
}

hdoj 2544 最短路 【最短路径模板题】

标签：最短路

原文地址：http://blog.csdn.net/shengweisong/article/details/41013987