好坑啊!!特别注意判断如果当下面数据
0 2
0=0
0>0
输出是CONFLICT
下面的是正确的
#include<cstdio>#include<iostream>#include<algorithm>#include<cstring>#include<queue>using namespace std;int set[200100],head[200100],shuchu[200100],rudu[200100];int n,m,cnt,flag,sum;struct node{ int u,v,next; char ch;} edge[100000],q[200000];int find(int x){ if(set[x]!=x) set[x]=find(set[x]); return set[x];}void get(int x,int y){ int xx=find(x); int yy=find(y); if(xx!=yy) set[xx]=yy;}void add(int u,int v){ edge[cnt].u=u; edge[cnt].v=v; edge[cnt].next=head[u]; head[u]=cnt++;}void topu(){ flag=0; queue<int>q; for(int i=0; i<n; i++) { int t=find(i); if(!rudu[t]&&set[t]==i) { q.push(t); } } while(!q.empty()) { int l=q.front(); q.pop(); sum--; if(!q.empty()) flag=1; int v; for(v=head[l]; v!=-1; v=edge[v].next) { int u=edge[v].v; rudu[u]--; if(!rudu[u]) q.push(u); } }} int main() { while(~scanf("%d %d",&n,&m)) { cnt=0; int e=0; sum=n; memset(head,-1,sizeof(head)); memset(rudu,0,sizeof(rudu)); for(int i=0; i<=200100; i++) set[i]=i; for(int i=0; i<m; i++) { cin>>q[i].u>>q[i].ch>>q[i].v; if(q[i].ch=='=') { get(q[i].u,q[i].v); sum--; } } for(int i=0; i<m; i++) { if(q[i].ch=='=') continue; int c=find(q[i].u); int d=find(q[i].v); if(c==d) e=1; if(q[i].ch=='>') { add(c,d); rudu[d]++; } else if(q[i].ch=='<') { add(d,c); rudu[c]++; } } topu(); if(sum>0||e) cout<<"CONFLICT"<<endl; else if(flag==1) cout<<"UNCERTAIN"<<endl; else cout<<"OK"<<endl; } return 0; }
但是还是写了一个TLE的
#include<cstdio>#include<iostream>#include<algorithm>#include<cstring>#include<queue>using namespace std;int set[200100],head[200100],shuchu[200100],rudu[200100];int n,m,cnt,flag,l;struct node{ int u,v,next; char ch;} edge[100000],q[200000];int find(int x){ if(set[x]!=x) set[x]=find(set[x]); return set[x];}void get(int x,int y){ int xx=find(x); int yy=find(y); if(xx!=yy) set[xx]=yy;}void add(int u,int v){ edge[cnt].u=u; edge[cnt].v=v; edge[cnt].next=head[u]; head[u]=cnt++;}void topu(){ flag=0; for(int i = 0; i<n; i++) { int s=0; for(int j=0; j<n; j++) { int t=find(j); if(rudu[t]==0&&set[t]==j) s++; } if(s>1) { flag=1; } for(int j = 0; j<n; j++) { int t=find(j); if(rudu[t]==0&&set[t]==j) { rudu[j]--; l--; for(int pp = head[j]; pp != -1; pp = edge[pp].next) { rudu[edge[pp].v]--; } break; } } }} int main() { while(~scanf("%d %d",&n,&m)) { cnt=0; int e=0; l=n; memset(head,-1,sizeof(head)); memset(rudu,0,sizeof(rudu)); for(int i=0; i<=200100; i++) set[i]=i; for(int i=0; i<m; i++) { cin>>q[i].u>>q[i].ch>>q[i].v; if(q[i].ch=='=') { get(q[i].u,q[i].v); l--; } } for(int i=0; i<m; i++) { if(q[i].ch=='=') continue; int c=find(q[i].u); int d=find(q[i].v); if(c==d) e=1; if(q[i].ch=='>') { add(c,d); rudu[d]++; } else if(q[i].ch=='<') { add(d,c); rudu[c]++; } } topu(); if(l>0||e) cout<<"CONFLICT"<<endl; else if(flag==1) cout<<"UNCERTAIN"<<endl; else cout<<"OK"<<endl; } return 0; }