zoj 1406 poj 1251 Jungle Roads

#include <iostream>#include <cstring>#include <cstdio>#include <cstdlib>using namespace std;const int MAXN = 27;const int MAXM = 100;struct Edge{int u, v, w;};Edge edges[MAXM];int parent[MAXN];int kcount[MAXN];int Maxweight;int n, m;void UFset(){int i;for (i = 0; i < n; ++i){parent[i] = i;kcount[i] = 1;}}int Find_Parent( int x ){int s;for(s = x; s != parent[s]; s = parent[s]);while (s != x){int tmp = parent[x];parent[x] = s;x = tmp;}return s;}void Union(int u, int v){int r1 = Find_Parent( u );int r2 = Find_Parent( v );if(kcount[r1] > kcount[r2]){parent[r2] = r1;kcount[r1] += kcount[r2];}else{parent[r1] = r2;kcount[r2] += kcount[r1];}}void Kruskal(){int i;UFset();int num  = 0;int u, v;for (i = 0; i < m; ++i){u = edges[i].u;v = edges[i].v;if(Find_Parent(u) != Find_Parent(v)){Maxweight += edges[i].w;num++;Union(u, v);}if(num >= n-1)return;}}int cmp (const void* a, const void* b){Edge* aa = ( Edge* )a;Edge* bb = ( Edge* )b;if(aa->w > bb->w)return 1;elsereturn -1;}int main(){char ch;int i, j, k;int u, v, w;while (cin>>n){if(n == 0)break;memset(parent, 0, sizeof(parent));int EdgeNum = 0;//严重错误！忘了在这里初始化，注意细节！！！for (i = 0; i < n-1; ++i){cin>>ch>>k;u = ch - 'A';for (j = 0; j < k; ++j){cin>>ch>>w;v = ch - 'A';edges[ EdgeNum ].u = u;edges[ EdgeNum ].v = v;edges[ EdgeNum++ ].w = w;}}m = EdgeNum;qsort(edges, m, sizeof(edges[0]), cmp);Maxweight = 0;Kruskal();cout<<Maxweight<<endl;}return 0;}