bzoj1116: [POI2008]CLO

 1 #include<iostream>
 2 #include<cstring>
 3 #include<algorithm>
 4 #include<cstdio>
 5 #include<cmath>
 6 #define maxn 100005
 7 using namespace std;
 8 int n,m;
 9 int fa[maxn];
10 bool mark[maxn];
11 int read()
12 {
13     int x=0; char ch; bool bo=0;
14     while (ch=getchar(),ch<‘0‘||ch>‘9‘) if (ch==‘-‘) bo=1;
15     while (x=x*10+ch-‘0‘,ch=getchar(),ch>=‘0‘&&ch<=‘9‘) ;
16     if (bo) return -x; return x;
17 }
18 int find(int x)
19 {
20     if (fa[x]!=x) fa[x]=find(fa[x]);
21     return fa[x];
22 }
23 int main()
24 {
25     n=read(); m=read();
26     for (int i=1; i<=n; i++) fa[i]=i;
27     for (int i=1; i<=m; i++)
28     {
29         int u=read(),v=read();
30         int q=find(u),p=find(v);
31         if (q!=p)
32         {
33             fa[q]=p; mark[p]=mark[p] | mark[q];
34         }
35         else
36         mark[q]=1;
37     }
38     for (int i=1; i<=n; i++) 
39     if (!mark[find(i)]) 
40     {
41         printf("NIE");
42         return 0;
43     }
44     printf("TAK"); return 0;
45 }