C

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

#define ll     long long
#define ff     first
#define ss     second
#define pb     push_back

int main()
{
     int n, m, h, k;
     cin>>n>>m>>h>>k;

     string s;
     cin>>s;

     map<pair<int, int>, int> mp;

     for(int i=0; i<m; i++)
     {
         int x, y;
         cin>>x>>y;

         mp[{x, y}] = 1;
     }

     int i=0;
     int x=0, y=0;
     while(i < n)
     {
         h--;
         if(h < 0)      break;

         if(s[i] == 'L')        x--;
         if(s[i] == 'D')        y--;
         if(s[i] == 'U')        y++;
         if(s[i] == 'R')        x++;

         if(mp[{x, y}] && h<k)
            h = max(h, k), mp[{x, y}] = 0;

         i++;
     }

     if(i == n)
        cout<<"Yes\n";
     else
        cout<<"No\n";
}