#include <iostream>
void aaa(int *a,int start,int end){
  if(start<end){
	for(int i=start;i<end; i++){
      if(a[i]>a[i+1]){
        int tmp=a[i];
        a[i]=a[i+1];
        a[i+1]=tmp;
      }
    }
    aaa(a,start,end-1);
  }
}

int main(void){
  int x[5];
  x[0]=0;
  x[1]=0;
  x[2]=0;
  x[3]=0;
  x[4]=0;
  std::cin >> x[0] >> x[1] >> x[2] >> x[3];
  aaa(x,0,3);
  //std::cout << x[0] << x[1] << x[2] << x[3];
  if((x[3]-x[0]==3)&&(x[2]-x[1]==1)) std::cout << "Yes"  << std::endl;
  else std::cout << "No"  <<std::endl;
}