#include <bits/stdc++.h>

using namespace std;

using vec = vector<int>;
using vvec = vector<vec>;
using bvec = vector<bool>;
using pii = pair<int,int>;

#define VECT(T) vector<T>
#define PRINT(vector) for(auto ele : vector) cout << ele << " "; cout << "\n";
#define RANGE(vector) vector.begin(), vector.end()

constexpr int E9 = 1e9 + 7;
constexpr int NUFFIN = 1023;

extern void setHintLen(int l);
extern void setHint(int i, int j, bool b);
extern int getLength();
extern bool getHint(int j);
extern bool goTo(int x);

void bettersethint(int p, int x, int y) {
	for(int i = 0 ; i < 10 ; ++i) {
		setHint(p, i, x&1);
		x >>= 1;
	}
	for(int i = 0 ; i < 10 ; ++i) {
		setHint(p, 10+i, x&1);
		x >>= 1;
	}
}

pii bettergethint(int p) {
	int x = 0, y = 0;
	for(int i = 0 ; i < 10 ; ++i) {
		x <<= 1;
		x += (int)getHint(i);
	}
	for(int i = 0 ; i < 10 ; ++i) {
		x <<= 1;
		x += (int)getHint(10+i);
	}
	return {x,y};
}

void dfs(vvec &g, int p, int par, pii next) {
	int n = (int)g[p].size();

	for(int i = 0 ; i < n ; ++i) {
		pii nx = next;
		if(i+1 < n) nx = {p, g[p][i+1]};
		dfs(g, g[p][i], p, nx);
	}

	if(n == 1) bettersethint(p, next.first, next.second);
	else bettersethint(p, g[p][0], NUFFIN);
}

void assignHints(int subtask , int N, int A[], int B[]) {
	setHintLen(20);
	vvec g(N);
	for(int i = 0 ; i < N-1 ; ++i) {
		g[A[i]].push_back(B[i]);
		g[B[i]].push_back(A[i]);
	}
}

void speedrun(int subtask, int N, int start) {
	int p = start;
	vec par(N, -1);
	while(p != -1) {
		auto [x,y] = bettergethint(p);
		if(x == NUFFIN) break;
		if(y == NUFFIN) {
			assert(goTo(x));
			par[x] = p;
			p = x;
		} else {
			while(p != -1 && p != x) {
				assert(goTo(par[p]));
				p = par[p];
			}
			assert(p != -1);

			assert(goTo(y));
			par[y] = p;
			p = y;
		}
	}
}