hdu 1874 畅通工程续（bellman-ford，dijkstra）

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bellman-ford：

#include <stdio.h>#define INF 99999999int u[2200],v[2200],w[2200];int dis[210];int main(){    int n,m,i,k;    while(scanf("%d %d",&n,&m) != EOF)    {        for(i = 0; i < m; ++i)        {            scanf("%d %d %d",&u[i],&v[i],&w[i]);            u[i+m] = v[i];            v[i+m] = u[i];            w[i+m] = w[i];        }        int start,end;        scanf("%d %d",&start,&end);        for(i = 0; i < n; ++i)            dis[i] = INF;        dis[start] = 0;        for(k = 0; k < n; ++k)            for(i = 0; i < 2*m; ++i)                if(dis[v[i]] > dis[u[i]] + w[i])                    dis[v[i]] = dis[u[i]] + w[i];        if(dis[end] < INF)            printf("%d\n",dis[end]);        else            printf("-1\n");    }    return 0;}

dijkstra：

#include <iostream>#include <cstring>using namespace std;#define INF 99999999int map[200][200];int dis[200];int book[200];int n,m;int main(){    int S,T,i,k,j,x,y,z;    while(cin >> n >> m)    {        for(i = 0; i < n; ++i)            for(j = 0; j < n; ++j)                if(i == j) map[i][j] = 0;                else map[i][j] = INF;        for(i = 0; i < m; ++i)        {            cin >> x >> y >> z;            if(z < map[x][y])                map[x][y] = map[y][x] = z;        }        memset(book,0,sizeof(book));        cin >> S >> T;        for(i = 0; i < n; ++i)            dis[i] = map[S][i];        book[S] = 1;        int min = INF;        int u,v;        for(k = 0; k < n; ++k)        {            min = INF;            for(i = 0; i < n; ++i)                if(!book[i] && min > dis[i]){ min = dis[i]; u = i;}            book[u] = 1;            for(v = 0; v < n; ++v)                dis[v] = dis[v] < dis[u]+map[u][v] ? dis[v]:dis[u]+map[u][v];        }        if(dis[T] != INF)            cout << dis[T] << endl;        else            cout << "-1" << endl;    }    return 0;}

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