P1955 [NOI2015] 程序自动分析（并查集）

相等放并查集里，不等直接判断

#include<bits/stdc++.h>
using namespace std;
#define x first
#define y second
typedef pair<int,int> PII;
typedef long long ll;
typedef unsigned long long ull;
typedef unsigned int uint;
typedef vector<string> VS;
typedef vector<int> VI;
typedef vector<vector<int>> VVI;
vector<int> vx;
inline int mp(int x) {return upper_bound(vx.begin(),vx.end(),x)-vx.begin();}
inline int log_2(int x) {return 31-__builtin_clz(x);}
inline int popcount(int x) {return __builtin_popcount(x);}
inline int lowbit(int x) {return x&-x;}
const int N = 1e5+10;
//注意有n条指令至多有2*n个点
int f[N<<1];
int find(int u)
{
    if(f[u] == u) return u;
    return f[u] = find(f[u]);
}
void merge(int u,int v)
{
    int f1 = find(u), f2 = find(v);
    if(f1 != f2) f[f1] = f2;
}
void solve()
{
    vx.clear();
    int n;
    cin>>n;
    vector<array<int,3>> tmp(n);
    vector<PII> pd;
    for(int i=1;i<=2*n;++i) f[i] = i;
    for(int i=0;i<n;++i)
    {
        int u,v,e;
        cin>>u>>v>>e;
        tmp[i] = {u,v,e};
        vx.push_back({u});
        vx.push_back({v});
    }
    sort(vx.begin(),vx.end());
    for(int i=0;i<n;++i)
    {
        auto [u,v,e] = tmp[i];
        if(e) merge(mp(u),mp(v));
        else pd.push_back({mp(u),mp(v)});
    }
    bool ok = true;
    for(auto [s,t]:pd)
    {
        if(find(s) == find(t)) ok = false;
    }
    cout<<(ok?("YES\n"):("NO\n"));
}
int main()
{
	ios::sync_with_stdio(false);
	cin.tie(0);
	int T = 1;
	cin>>T;
	while(T--)
	{
		solve();
	}
}