UVa 10842 Traffic Flow（最大生成树）

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这道题，第一wa了，因为我没有注意它可能是存在自环以及重边的

很水的一道最大生成树的题

代码如下：

#include <cstdio>#include <cstring>#include <algorithm>using namespace std;const int N = 110;const int INF = -1;const int INFB = 10000;int T, n, m, g[N][N], p[N], pa;void prim() {    int d[N], v, mi;    bool vis[N];    for ( int i = 0; i <= n; ++i ) d[i] = p[i] = -1;    memset(vis, 0, sizeof(vis));    d[0] = 0, pa = 0;    for ( int u = 0; u < n; ++u ) {        mi = INF;        for ( int i = 0; i < n; ++i ) if ( !vis[i] && d[i] > mi ) mi = d[i], v = i;        vis[v] = true;        pa += mi;        for ( int i = 0; i < n; ++i ) if ( !vis[i] && d[i] < g[v][i] ) p[i] = v, d[i] = g[v][i];    }}int main(){    int idx = 1;    scanf("%d", &T);    while( T-- ) {        scanf("%d%d", &n, &m);        for ( int i = 0; i < n; ++i ) for ( int j = 0; j < n; ++j ) g[i][j] = -1;        while ( m-- ){            int a, b, c;            scanf("%d%d%d", &a, &b, &c);            if ( a != b )                g[a][b] = g[b][a] = max( c, g[a][b] );        }        prim();        int ans = INFB;         for ( int i = 1; i < n; ++i )             ans = min( ans, g[i][p[i]] );        printf("Case #%d: %d\n", idx++, ans);    }}