#include <bits/stdc++.h>                                                                              
using namespace std;                                                                                  
using ll = long long;                                                                                 
template<class T>bool chmin(T &a, const T &b) { if (b<a) { a=b; return 1; } return 0; }               
template<class T>bool chmax(T &a, const T &b) { if (a<b) { a=b; return 1; } return 0; }               
#define rep(i,n) for (int i=0; i< (n); ++i)                                                           
typedef pair<int, int> P;                                                                             
                                                                                                      
int main() {                                                                                          
  int a, b, c, d;                                                                                     
  cin >> a >> b >> c >> d;                                                                            
  bool winTakahashi = true;                                                                           
  while (true) {                                                                                      
    c -= b;                                                                                           
    if (c <= 0) {                                                                                     
      winTakahashi = true;                                                                            
      break;                                                                                          
    }                                                                                                 
    a -= d;                                                                                           
    if (a <= 0) {                                                                                     
      winTakahashi = false;                                                                           
      break;                                                                                          
    }                                                                                                 
  }                                                                                                   
  if (winTakahashi) {                                                                                 
    cout << "Yes" << endl;                                                                            
  } else {                                                                                            
    cout << "No" << endl;                                                                             
  }                                                                                                   
                                                                                                      
  return 0;                                                                                           
}   

Measured memory_bytes: 3592