#include <bits/stdc++.h>
#define int long long
using namespace std;

int n, m, isLeaf[100005], bit[2][2][100005], X, Y;
string s[100005];
vector<int> G[100005];

int cal(int T, string t){
  
  if( t[3] == '&' ){
    if( t[4] == 'X' ) return T & X;
    if( t[4] == 'Y' ) return T & Y;
  }
  
  if( t[3] == '|' ){
    if( t[4] == 'X' ) return T | X;
    if( t[4] == 'Y' ) return T | Y;
  }

  if( t[3] == '^' ){
    if( t[4] == 'X' ) return T ^ X;
    if( t[4] == 'Y' ) return T ^ Y;
  }
  
}

void dfs(int x, int px, int T){
  
  int nT = 0;
  
  if( x != 0 ) nT = cal( T, s[x] );
  
  int flag = 1;
  
  for(int nx : G[x] ){
    
    if( nx == px ) continue;
    
    flag = 0;

    dfs( nx, x, nT );
  }
  
  isLeaf[x] = flag;
  
  bit[X][Y][x] = nT;
  
}

int get(int I, int x){
  if( I == 0 ) return bit[0][1][x];
  if( I == 1 ) return bit[1][0][x];
  return bit[1][1][x];
}

int MM[3][3][3][100005];

int minmax(int x, int px, int dep, int I1, int I2, int I3){
  
  if( isLeaf[x] ){
    
    int res = 0;
    
    res |= get(I1, x);
    res = res << 1;
    res |= get(I2, x);
    res = res << 1;
    res |= get(I3, x);
    
    return MM[I1][I2][I3][x] = res;
  }
  
  int res;
  
  if( dep % 2 == 0 ) res = 0;
  else res = 10;

  for(int nx : G[x] ){
    
    if( nx == px ) continue;
    
    if( dep % 2 == 0 ) res = max( res, minmax( nx, x, dep + 1, I1, I2, I3 ));
    else res = min( res, minmax( nx, x, dep + 1, I1, I2, I3 ));
    
  }  
  
  return MM[I1][I2][I3][x] = res;
}

signed main(){
  
  cin>>n>>m;
  
  for(int i=1;i<n;i++) cin>>s[i];
  
  for(int i=0;i<n-1;i++){
    int u, v;
    cin>>u>>v;
    G[u].push_back(v);
    G[v].push_back(u);
  }
  
  for(X=0;X<=1;X++){
    
    for(Y=0;Y<=1;Y++){
      
      dfs( 0, -1, 0 );
      
    }
    
  }
  
  minmax( 0, -1, 0, 0, 1, 2 );
  minmax( 0, -1, 0, 0, 2, 1 );
  minmax( 0, -1, 0, 1, 0, 2 );
  minmax( 0, -1, 0, 1, 2, 0 );
  minmax( 0, -1, 0, 2, 0, 1 );
  minmax( 0, -1, 0, 2, 1, 0 );
  
  for(int i=0;i<m;i++){
    
    cin>>X>>Y;
    
    int ans = 0;
    
    int used[3] = {};
    vector<int> pri;
    
    for(int j=16;j>=0;j--){
      
      if( ( ( X >> j ) & 1 ) == 0 && ( Y >>j & 1 ) == 1 ){
	
	if( used[0] ) continue;
	used[0] = 1;
	
	pri.push_back(0);
      }

      if( ( ( X >> j ) & 1 ) == 1 && ( Y >>j & 1 ) == 0 ){
	
	if( used[1] ) continue;
	used[1] = 1;

	pri.push_back(1);
      }

      if( ( ( X >> j ) & 1 ) == 1 && ( Y >>j & 1 ) == 1 ){
	
	if( used[2] ) continue;
	used[2] = 1;

	pri.push_back(2);
      }
      
    }
    
    for(int j=0;j<3;j++)
      if( used[j] == 0 ) pri.push_back(j);
    
    int I1 = pri[0], I2 = pri[1], I3 = pri[2];
    
    for(int j=0;j<17;j++){
      
      if( ( ( X >> j ) & 1 ) == 0 && ( Y >>j & 1 ) == 1 ){
	if( I1 == 0 ) ans |= ( MM[I1][I2][I3][0] >> 2 & 1 ) << j;
	if( I2 == 0 ) ans |= ( MM[I1][I2][I3][0] >> 1 & 1 ) << j;
	if( I3 == 0 ) ans |= ( MM[I1][I2][I3][0] >> 0 & 1 ) << j;
      }
      
      if( ( ( X >> j ) & 1 ) == 1 && ( Y >>j & 1 ) == 0 ){
	if( I1 == 1 ) ans |= ( MM[I1][I2][I3][0] >> 2 & 1 ) << j;
	if( I2 == 1 ) ans |= ( MM[I1][I2][I3][0] >> 1 & 1 ) << j;
	if( I3 == 1 ) ans |= ( MM[I1][I2][I3][0] >> 0 & 1 ) << j;
      }
      
      if( ( ( X >> j ) & 1 ) == 1 && ( Y >>j & 1 ) == 1 ){
	if( I1 == 2 ) ans |= ( MM[I1][I2][I3][0] >> 2 & 1 ) << j;
	if( I2 == 2 ) ans |= ( MM[I1][I2][I3][0] >> 1 & 1 ) << j;
	if( I3 == 2 ) ans |= ( MM[I1][I2][I3][0] >> 0 & 1 ) << j;
      }
            
    }
        
    cout<<ans<<endl;
  }
  
  return 0;
}



Measured memory_bytes: 32172