hdu3729二分图匹配

思路：求最大可能的说真话的人数，也就是匹配数，因为一个人说的是真话的前提是可以找到正确的理论支撑点，也就是在他所说的话中,l <= x <= r,至少存在一种关系是真的，也就是对于m属于[l,r] && m != x,使得真的有x < m || x > m,这个也就是匹配关系；

/*****************************************
Author      :Crazy_AC(JamesQi)
Time        :2015
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 <stdio.h>
#include <string.h>
#include <math.h>
#include <stdlib.h>
#include <limits.h>
using namespace std;
#define MEM(a,b) memset(a,b,sizeof a)
#define pk push_back
template<class T> inline T Get_Max(const T&a,const T&b){return a < b?b:a;}
template<class T> inline T Get_Min(const T&a,const T&b){return a < b?a:b;}
typedef long long ll;
typedef pair<int,int> ii;
const int inf = 1 << 30;
const int INF = 0x3f3f3f3f;
const int MOD = 1e9 + 7;
int uN,vN;
const int maxn = 6e6 + 10;
int head[100010];
struct Edge{
	int to,nxt;
}E[maxn];
int tol;
int n;
vector<int> vec;
void addedge(int u,int v){
	E[tol].to = v;
	E[tol].nxt = head[u];
	head[u] = tol++;
}
int mark[100010],link[100010];
bool Search_P(int u){
	for (int i = head[u];i != -1;i = E[i].nxt){
		int v = E[i].to;
		if (!mark[v]){
			mark[v] = 1;
			if (link[v] == -1 || Search_P(link[v])){
				link[v] = u;
				return true;
			}
		}
	}
	return false;
}
inline int Hungary(){
	int ret = 0;
	MEM(link, -1);
	for (int i = n - 1;i >= 0;i--){
		MEM(mark, 0);
		if (Search_P(i)){
			ret++;
			vec.push_back(i);
		}
	}
	return ret;
}

int main()
{	
	// ios::sync_with_stdio(false);
	// freopen("in.txt","r",stdin);
	// freopen("out.txt","w",stdout);
	int T;
	cin >> T;
	while(T--){
		scanf("%d",&n);
		int a,b;
		MEM(head, -1);
		tol = 0;
		for (int i = 0;i < n;i++){
			scanf("%d%d",&a,&b);
			for (int j = a;j <= b;++j)
				addedge(i,j);
		}
		vec.clear();
		// int ans;
		printf("%d\n",Hungary());
		sort(vec.begin(),vec.end());
		for (int i = 0;i < vec.size();i++){
			printf("%d%c",vec[i] + 1,(i == vec.size() - 1)?'\n':' ');
		}
	}
	return 0;
}