POJ 1797 Heavy Transportation

题意:有1~n个顶点，找所有连通的路中承载重量最大的那条路径

分析:首先想到的贪心，就是每次找最大的那条，就是Dijkstra变形嘛，跟我做的上一道题有点像，贴下一道题的链接：https://www.cnblogs.com/ducklu/p/9188670.html

这一道题是每一次找最大然后收录，然后松弛的时候也有变化

#include <iostream>
#include <cstring>
#include <cstdio>
#include <algorithm>
#include <cmath>
#define MAXVERTEXNUM 1010
//#define INF 99999999
using namespace std;

int D[MAXVERTEXNUM][MAXVERTEXNUM], dist[MAXVERTEXNUM];
int Nv, Ne;

void Dijkstra()
{
    int Visited[MAXVERTEXNUM];
    memset(Visited, 0, sizeof(Visited));
    for (int i = 2; i <= Nv; ++i)
    {
        if (D[1][i])
            dist[i] = D[1][i];
        else
            dist[i] = 0;
    }
    Visited[1] = 1;
    dist[1] = 0;

    for (int i = 1; i <= Nv; ++i)
    {
        int MAXDist = -1, pos;
        for (int j = 2; j <= Nv; ++j)
            if (!Visited[j] && dist[j] > MAXDist)
            {
                MAXDist = dist[j];
                pos = j;
            }

        Visited[pos] = 1;

        for (int j = 2; j <= Nv; ++j)
        {
            if (!Visited[j] && D[pos][j])
                dist[j] = max(dist[j], min(dist[pos], D[pos][j]));
        }
    }
}

int main()
{
    ios::sync_with_stdio(false);

    int cas;
    cin >> cas;
    for (int k = 1; k <= cas; ++k)
    {
        memset(D, 0, sizeof(D));
        cin >> Nv >> Ne;
        for (int i = 1; i <= Ne; ++i)
        {
            int V1, V2, Edge;
            cin >> V1 >> V2 >> Edge;
            D[V1][V2] = D[V2][V1] = Edge;
        }

        Dijkstra();
        printf("Scenario #%d:
%d

", k, dist[Nv]);
    }

    return 0;
}