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fn dfs(i: i32, sum: i32) -> bool {
   let k = 10;
   let n = 10;

   if (i == n) {
      return sum == k;
   }

   if (dfs(i + 1, sum)) {
      return true;
   }

   if (dfs(i + 1, sum + i)) {
      return true;
   }
   return false;
}


fn main() {
   if (dfs (0, 0)) {
      println!("yes");
   } else {
      println!("no");
   }
}