P1955 [NOI2015]程序自动分析[离散化+并查集]

一看就是离散化，先去满足相等的条件，相等即为两点联通，或者说在同一个集合内。再看不相等，只有两元素在同一集合才不满足。裸的disjoint-set直接上，常数巨大什么的不管啦。

 #include<iostream>
 #include<cstdio>
 #include<cstring>
 #include<cmath>
 #include<algorithm>
 #include<queue>
 #define dbg(x) cerr<<#x<<" = "<<x<<endl
 #define ddbg(x,y) cerr<<#x<<" = "<<x<<"   "<<#y<<" = "<<y<<endl
 using namespace std;
 typedef long long ll;
 template<typename T>inline char MIN(T&A,T B){return A>B?A=B,:;}
 template<typename T>inline char MAX(T&A,T B){return A<B?A=B,:;}
 template<typename T>inline T _min(T A,T B){return A<B?A:B;}
 template<typename T>inline T _max(T A,T B){return A>B?A:B;}
 template<typename T>inline T read(T&x){
     x=;int f=;char c;while(!isdigit(c=getchar()))if(c=='-')f=;
     while(isdigit(c))x=x*+(c&),c=getchar();return f?x=-x:x;
 }
 const int N=+;
 struct Remilia_Scarlet{
     int x,y,d;
     inline bool operator <(const Remilia_Scarlet&A)const{
         return d>A.d;
     }
 }q[N];
 int A[N<<],fa[N<<];
 int T,n,m,fx,fy,flag;
 inline int Get(int x){return fa[x]^x?fa[x]=Get(fa[x]):x;}

 int main(){//freopen("test.in","r",stdin);//freopen("test.out","w",stdout);
     read(T);while(T--){
         read(n);m=;flag=;
         for(register int i=;i<=n;++i)A[++m]=read(q[i].x),A[++m]=read(q[i].y),read(q[i].d);
         sort(A+,A+m+);m=unique(A+,A+m+)-A-;sort(q+,q+n+);
         for(register int i=;i<=m;++i)fa[i]=i;
         for(register int i=;i<=n;++i){
             if(q[i].d){
                 fx=Get(lower_bound(A+,A+m+,q[i].x)-A),fy=Get(lower_bound(A+,A+m+,q[i].y)-A);
                 if(fx^fy)fa[fx]=fy;//ddbg(fx,fy);
             }
             else{
                 fx=Get(lower_bound(A+,A+m+,q[i].x)-A),fy=Get(lower_bound(A+,A+m+,q[i].y)-A);
                 if(fx^fy)continue;
                 flag=;break;
             }
         }
         flag?printf("NO\n"):printf("YES\n");
     }
     return ;
 }