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来源：互联网发布：进出口银行待遇知乎编辑：程序博客网时间：2024/06/16 01:48

离线的并查集

水啊水，昨天太2了

不过题意也够2的，这翻译啊

#include <cstdio>#include <cstring>#include <algorithm>using namespace std;struct EDGE{    int u, v, val;}edge[50000 + 1234];struct QUE{    int id, val;}l[10000 + 123];int n, m, q;int p[10000 + 123];int num[10000 + 123];int cou[10000 + 123];bool cmp(EDGE x, EDGE y){    return x.val < y.val;}bool cmp2(QUE x, QUE y){    return x.val < y.val;}void init(){    for(int i = 1; i <= n; i++)    {        p[i] = i;        num[i] = 1;    }}int find(int k){    if(k != p[k])  p[k] = find(p[k]);    return p[k];}int Union(int a, int b){    a = find(a);    b = find(b);    if(a == b) return 0;    int t = num[a] * num[b];    p[b] = a;    num[a] += num[b];    num[b] = 0;    return t;}int main(){    while(scanf("%d%d%d", &n, &m, &q) != EOF)    {        for(int i = 0; i < m; i++)  scanf("%d%d%d",&edge[i].u, &edge[i].v, &edge[i].val);        sort(edge, edge + m, cmp);        for(int i = 0; i < q; i++)        {            scanf("%d", &l[i].val);            l[i].id = i;        }        sort(l, l + q, cmp2);        init();        int begin = 0;        int ans = 0;        for(int i = 0; i < q; i++)        {            while(edge[begin].val <= l[i].val && begin < m)            {                ans += Union(edge[begin].u, edge[begin].v);                begin++;            }            cou[l[i].id] = ans;        }        for(int i = 0; i < q; i++)        printf("%d\n", cou[i]);    }    return 0;}