hdu5101Select(树状数组求组合数)

这题不同于一般的求组合数的地方就是不能同班,所以在插入的时候就只能一个班整体的插入和整体的查询。

/*****************************************
Author      :Crazy_AC(JamesQi)
Time        :2016
File Name   :
*****************************************/
// #pragma comment(linker, "/STACK:1024000000,1024000000")
#include <iostream>
#include <algorithm>
#include <iomanip>
#include <sstream>
#include <string>
#include <stack>
#include <queue>
#include <deque>
#include <vector>
#include <map>
#include <set>
#include <cstdio>
#include <cstring>
#include <cmath>
#include <cstdlib>
#include <climits>
using namespace std;
#define MEM(x,y) memset(x, y,sizeof x)
#define pk push_back
#define lson rt << 1
#define rson rt << 1 | 1
#define bug cout << "BUG HERE\n"
typedef long long LL;
typedef unsigned long long ULL;
typedef pair<int,int> ii;
typedef pair<ii,int> iii;
const double eps = 1e-10;
const int inf = 1 << 30;
const int INF = 0x3f3f3f3f;
const int MOD = 1e9 + 7;
int nCase = 0;
const int maxn = 1010*100;
LL k, n;
LL cls[1010][101];
int num[1010];
LL tmp[1010*100];
int top;
LL sum[1010*100];
int lowbit(int x) {
	return x & (-x);
}
void add(int x, LL val) {
	while(x < maxn) {
		sum[x] += 1LL*val;
		x += lowbit(x);
	}
}
int getsum(int x) {
	LL ret = 0LL;
	while(x > 0) {
		ret += sum[x];
		x -= lowbit(x);
	}
	return ret;
}
void insert(int x) {
	for (int i = 0;i < num[x];++i) {
		LL val = cls[x][i];
		int pos = lower_bound(tmp, tmp + top, val) - tmp + 1;
		add(pos, 1);
	}
}
LL query(int x) {
	LL ret = 0LL;
	for (int i = 0;i < num[x];++i) {
		LL val = cls[x][i];
		int pos = lower_bound(tmp, tmp + top, k - val + 1) - tmp + 1;
		ret += 1LL*(getsum(maxn-10) - getsum(pos - 1));
	}
	return ret;
}
int main(int argc, const char * argv[])
{	
	// freopen("in.txt","r",stdin);
	// freopen("out.txt","w",stdout);
	int t;
	scanf("%d",&t);
	while(t--) {
		memset(sum, 0,sizeof sum);
		top = 0;
		scanf("%lld%lld",&n,&k);
		for (int i = 1;i <= n;++i) {
			scanf("%d",&num[i]);
			for (int j = 0;j < num[i];++j) {
				scanf("%lld",&cls[i][j]);
				tmp[top++] = cls[i][j];
			}
		}
		sort(tmp, tmp + top);
		top = unique(tmp, tmp + top) - tmp;
		insert(1);
		LL ans = 0LL;
		for (int i = 2;i <= n;++i) {
			ans += query(i);
			insert(i);
		}
		cout << ans << endl;
	}
	return 0;
}


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