#include <stdio.h>

int main()
{
   int found13;    // 1 => found a 13
   int value;      // the value just read
   int howmany;    // howmany values were read


   found13 = 0;    // haven't found it yet
   howmany = fscanf(stdin, "%d", &value);

   while (howmany == 1)
   {
      if (value == 13)
         found13 = 1;
      howmany = fscanf(stdin, "%d", &value);
   }

   if (found13)
      fprintf(stdout, "yes\n");
   else
      fprintf(stdout, "no\n");
   return(0);
}