POJ.1797 Heavy Transportation (Dijkstra变形)

POJ.1797 Heavy Transportation (Dijkstra变形)

题意分析

1. 给出n个点，m条边的城市网络，其中 x y d 代表由x到y(或由y到x)的公路所能承受的最大重量为d，求从1到n的所有通路中，所能经过的的最大重量的车为多少。
2.

代码总览

#include <cstdio>#include <cstring>#include <algorithm>#include <queue>#include <stack>#include <vector>#include <cmath>#define nmax 1005#define inf 1e8+7using namespace std;int t,n,m;int mp[nmax][nmax];int shortpath[nmax];bool visit[nmax];void dij(int s){    int cur = s;    memset(visit,0,sizeof(visit));    for(int i = 1;i<=n;++i){shortpath[i] = mp[cur][i];}    shortpath[cur] = 0;    visit[cur] = true;    for(int i = 1;i<=n-1 ;++i){        int minL = 0;        for(int j = 1;j<=n;++j){            if(!visit[j] && shortpath[j] != 0 && shortpath[j] >minL){                minL = shortpath[j];                cur = j;            }        }        visit[cur] = true;        for(int j = 1;j<=n;++j){            if(!visit[j]){                shortpath[j] = max(min(mp[cur][j],shortpath[cur]),shortpath[j]);            }        }    }}void init(){    scanf("%d %d",&n,&m);    for(int i = 1;i<=n;++i)        for(int j = 1;j<=n;++j)            mp[i][j] = 0;    for(int i = 1;i<=m;++i){        int sta,end,dis;        scanf("%d %d %d",&sta,&end,&dis);        mp[sta][end] = mp[end][sta] = dis;    }}int main(){    //freopen("in.txt","r",stdin);    int kase  = 1;    scanf("%d",&t);    for(int i = 1;i<=t;++i){        init();        dij(1);        printf("Scenario #%d:\n",kase++);        printf("%d\n\n",shortpath[n]);    }    return 0;}