hdu 3938 Portal离线并查集

题意搞得迷迷糊糊的

参考：http://blog.csdn.net/sdj222555/article/details/7439187

#include<iostream>
#include<cstdio>
#include<cstdlib>
#include<cstring>
#include<string>
#include<queue>
#include<algorithm>
#include<map>
#include<iomanip>
#define INF 99999999
#define MAXN 10005
using namespace std;

int fa[MAXN], num[MAXN];
long long out[MAXN];
int n, m, q;

//适用于正负整数
template <class T>
inline bool scan_d(T &ret) {
    char c; int sgn;
    if (c = getchar(), c == EOF) return 0; //EOF
    while (c != '-' && (c<'0' || c>'9')) c = getchar();
    sgn = (c == '-') ? -1 : 1;
    ret = (c == '-') ? 0 : (c - '0');
    while (c = getchar(), c >= '0'&&c <= '9') ret = ret * 10 + (c - '0');
    ret *= sgn;
    return 1;
}

struct node {
    int u, v, w;
    bool operator < (const node& a) const {
        return w < a.w;
    }
}edge[MAXN*10];

struct wen {
    int l, id;
    bool operator <(const wen &a) const {
        return l < a.l;
    }
}p[MAXN];

void init()
{
    for (int i = 1; i <= n; ++i) {
        fa[i] = i;
        num[i] = 1;
    }
}

int find(int x)
{
    if (fa[x] == x) return x;
    int t = find(fa[x]);
    fa[x] = t;
    return t;
}

int join(int x, int y)
{
    int fx = find(x);
    int fy = find(y);
    if (fx == fy) return 0;
    int t = num[fx] * num[fy];
    num[fx] += num[fy];
    num[fy] = 0; 
    fa[fy] = fx;
    return t;
}

int main()
{
    while (cin >> n >> m >> q) {
        init(); 
        for (int i = 1; i <= m; ++i){
            //cin >> edge[i].u >> edge[i].v >> edge[i].w;
            scan_d(edge[i].u);
            scan_d(edge[i].v);
            scan_d(edge[i].w);
        }
        sort(edge + 1, edge + m + 1);
        for (int i = 1; i <= q; ++i) {
            //cin >> p[i].l;
            scan_d(p[i].l);
            p[i].id = i;
        }
        sort(p+1,p+q+1);
        int pos = 1;
        long long ans = 0;
        for (int i = 1; i <= q; ++i) {
            while (pos <= m && edge[pos].w <= p[i].l) {
                ans += join(edge[pos].u,edge[pos].v);
                pos++;
            }
            out[p[i].id] = ans;
        }
        for (int i = 1; i <= q; ++i) {
            cout << out[i] << endl;
        }
    }
    return 0;
}