hdu 1233 还是畅通工程(最小生成树Kruskal)

/*Author: ACb0yDate: 2010年9月16日1:24:18Type: MST KruskalProblemId: hdu 1233 还是畅通工程Result: 2960115 2010-09-16 01:22:42 Accepted 1233 343MS 428K 1087 B G++ ACb0y */#include <iostream>using namespace std;int n, q;int g[110][110];int father[110];struct edge {int x;int y;int w;};edge edges[10100];int cmp(const void * a, const void * b) {edge * pa = (edge *) a;edge * pb = (edge *) b;return pa->w > pb->w ? 1 : -1;}int find(int x) {if (x != father[x]) {return find(father[x]);}return x;}int main() {int i, j;#ifndef ONLINE_JUDGEfreopen("1233.txt, "r", stdin);#endifwhile (cin >> n) {if (n == 0) break;q = n * (n - 1) / 2;for (i = 1; i <= q; i++) {int a, b, c;scanf("%d%d%d", &a, &b, &c);g[a][b] = g[b][a] = c;}int c = 0;for (i = 1; i <= n; i++) {for (j = i + 1; j <= n; j++) {edges[c].w = g[i][j];edges[c].x = i;edges[c].y = j;c++;}}qsort(edges, c, sizeof(edge), cmp);for (i = 1; i <= n; i++) {father[i] = i;}int ans = 0;for (i = 0; i < c; i++) {int x = find(edges[i].x);int y = find(edges[i].y);if (x != y) {ans += edges[i].w;father[x] = y;}}cout << ans << endl;}return 0;}