#include <stdio.h>
int main()
{
    char ch = getchar();
    while(ch)
    {
        if(ch>=0 && ch<=64)
        {
            printf("NO\n");
            break;
        }
        else if(ch>64 && ch<=90)
        {
          printf("YES\n");
          break;
        }
        else if(ch>=(64+32) && (ch<=90+32))
        {
            printf("YES\n");
            break;
        }
    }
    
    
    
    
    return 0;
}