UVa112.cc

#include<cstdio>
#define LL long long
bool go_tree(LL tar, LL cur, bool &isNIL){
  LL val;
  bool res = false, ll = false, rl = false;
  if(scanf("\n(%lld", &val)){
    res |= go_tree(tar, cur + val, ll);
    res |= go_tree(tar, cur + val, rl);
    res |= (ll && rl && tar == cur + val);
  }
  else isNIL = true;
  scanf("\n)");
  return res;
}

int main(){
  bool _;
  LL target;
  while(~scanf("%lld", &target))
    puts(go_tree(target, 0, _) ? "yes" : "no");
  return 0;
}