#include<stdio.h>
#include<stack>

namespace bikuhiku{
    template <typename _T> _T gtr(_T &_compare_x,_T &_compare_y) {
        return _compare_x > _compare_y ? _compare_x : _compare_y;
    }
    template <typename _T> _T les(_T &_compare_x,_T &_compare_y) {
        return _compare_x < _compare_y ? _compare_x : _compare_y;
    }
    template <typename _T> void get_int(_T &_data_x) {
        int _signal = 1;
        char _get_c;
        _data_x = 0;
        for(_get_c = getchar();_get_c < '0'||_get_c > '9';_get_c = getchar()) if(_get_c == '-') _signal = -1;
        for(;_get_c >= '0'&&_get_c <= '9';_get_c = getchar()) _data_x = (_data_x<<3)+(_data_x<<1)+(_get_c^48);
        _data_x *= _signal;
        return;
    }
    template <typename _T> void put_int(_T _data_x) {
        if(_data_x > 9) put_int(_data_x/10);
        putchar((_data_x%10)^48);
        return;
    }
}//申请一块命名空间；
using namespace bikuhiku;
using namespace std;
const int z = 16384-4096-2048;

struct line{
	int t, next;
} edge[z*5];
int cnt, head[z];
void adline(int &f,int &t) {
	edge[++cnt].next = head[f];
	edge[cnt].t = t;
	head[f] = cnt;
	return;
}

stack<int> stk;
int dfn[z], low[z], time;
int belong[z];
bool instk[z];
void tarjan(int &u) {
	dfn[u] = low[u] = ++time;
	stk.push(u);
	instk[u] = true;
	for(int i = head[u];i;i = edge[i].next) {
		if(!dfn[edge[i].t]) {//是树枝边；
			tarjan(edge[i].t);
			low[u] = les(low[u],low[edge[i].t]);
		} else if(instk[edge[i].t]) {//是返祖边；
			low[u] = les(low[u],dfn[edge[i].t]);
		}
	}
	if(low[u] == dfn[u]) {//构成强连通分量；
		int tmp;
		++belong[0];
		do {
			tmp = stk.top();
			stk.pop();
			instk[tmp] = false;
			belong[tmp] = belong[0];
		} while(tmp != u);
	}
	return;
}

int main() {
	//to do;
	return 0;
}