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#include <iostream>
#include <stack>
#include <fstream>
using namespace std;

int main() {
    const int H = 1;
    const int C = 12;
    const int O = 16;
    
    ifstream inputF("MASS.IN");
    
    string temp;

  if (inputF.good())
  {
    getline(inputF, temp);
  } else {
      cout << 0 << endl;
  }
  
  stack<char> st;
  
  int i = 0, count = 0, sum = 0, mult = 1;
  while (i < temp.length()) {
      if (temp[i] == '(') {
          sum += count;
          count = 0;
          st.push('(');
          i++;
      }
      
      if (temp[i] == ')') {
          st.pop();
          i++;
          
          if (temp[i] >= '2' && temp[i] <= '9' && i < temp.length()) {
              if (temp[0] == '(' && temp[temp.length()-2] == ')') {
                  sum += count;
                  sum *= temp[i]-'0';
                  count = 0;
              } else {
                  mult = temp[i]-'0';
              }
          }
          
          sum+=mult*count;
          mult = 1;
          count = 0;
      }
      
      if (temp[i] == 'H') {
            count += H;
            i++;
      } else if (temp[i] == 'C') {
            count += C;
            i++;
      } else if (temp[i] == 'O') {
            count += O;
            i++;
      } else if (temp[i] >= '2' && temp[i] <= '9') {
            switch (temp[i-1]) {
                case 'H':
                    count += H*(temp[i]-'0')-H;
                    break;
                case 'C':
                    count += C*(temp[i]-'0')-C;
                    break;    
                case 'O':
                    count += O*(temp[i]-'0')-O;
                    break;    
            }
            i++;
      }
  }

if (!st.empty()) {
     sum = 0;
}
  
  if (sum == 0) {
      sum = count;
  }
    
  ofstream outputF("MASS.OUT");
  outputF << sum;
  outputF.close();

    return 0;
}