#include <stdio.h>

int main() 
{
   int a,b,c;
   scanf("%d %d %d",&a,&b,&c);
   float Avg = (a + b +c) / 3;
   if(Avg < 60)
   {
    printf("YES");
   }
   else 
   {
    printf("NO");
   }
   
    return 0;
}