1. #include <stdio.h>
  2. int main(){
  3. int a,b,c,i=1;

  4. scanf("%d %d %d",&a,&b,&c);

  5. float e=(a+b+c)/3;

  6. if(e<60)printf("YES");

  7. else printf("NO");
  8. return 0;
  9. }