UVa11747 Heavy Cycle Edge (Kruskal)

来源：互联网发布：java视频点播系统编辑：程序博客网时间：2024/05/19 12:40

卡了一道题，想今天怎么都得过一道题，就先拿着开刀吧，比较简单的

#include <cstdio>#include <algorithm>#include <cstring>using namespace std;typedef long long ll;struct edge {    int u, v;    ll w;    bool is;}e[25010];int n, m, fa[1010];bool cmp( edge a, edge b ) { return a.w < b.w; }int find ( int x ) { return fa[x] == x ? x : fa[x] = find(fa[x]); }int main(){    while ( scanf("%d%d", &n, &m) != EOF  && !(!n && !m) ) {        bool f = false;        for ( int i = 0; i < m; e[i].is = 0, ++i ) scanf("%d%d%lld", &e[i].u, &e[i].v, &e[i].w);        sort( e, e + m, cmp );        for ( int i = 0; i < n; ++i ) fa[i] = i;        for ( int i = 0; i < m; ++i ) {            int x = e[i].u, y = e[i].v;            int a = find(x), b = find(y);            if ( a != b ) {                fa[a] = b;                e[i].is = true;            }        }        for ( int i = 0; i < m; ++i ) {            if ( !e[i].is ) {                if ( f ) printf(" ");                f = true;                printf("%lld", e[i].w);            }        }        if ( !f ) printf("forest");        printf("\n");    }}