uva 10048 - Audiophobia（floyd 的变形）

把Floyd算法变一下形就可以了

#include <iostream>
#include <algorithm>
#include <cstdio>
#include <cstring>
#include <cstdlib>
using namespace std;
const int maxn = 100+10;
const int INF = 0x7fffffff;
int m, n, qu;
int d[maxn][maxn];

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

int main()
{
    int CASE = 0;
    while(scanf("%d%d%d", &n, &m, &qu) != EOF && m && n && qu) {
        int a, b, c;
        for(int i = 0; i < 103; ++i)
            for(int j = 0; j < 103; ++j)
                d[i][j] = INF;
        for(int i = 0; i < m; ++i) {
            scanf("%d%d%d", &a, &b, &c);
            d[a][b] = c;
            d[b][a] = c;
        }
        floyd();
        int q, w;
        if(CASE != 0) printf("\n");
        printf("Case #%d\n", ++CASE);
        for(int i = 0; i < qu; ++i) {
            scanf("%d%d", &q, &w);
            if(d[q][w] == INF) printf("no path\n");
            else printf("%d\n", d[q][w]);
        }

    }
    return 0;
}