func_code_string: #include <bits/stdc++.h>   using namespace std;   int main() {     string s;     cin >> s;     stack<char> a;     int count = 0, flag = 0;     for (int i = 0; i < s.length(); i++) {       if (s[i] ==  {  || s[i] ==  [  || s[i] ==  <  || s[i] ==  ( )         a.push(s[i]);       else {         if (a.size() == 0) {           cout <<  Impossible ;           return 0;         }         if (a.top() ==  (  && s[i] !=  )  || a.top() ==  {  && s[i] !=  }  ||             a.top() ==  [  && s[i] !=  ]  || a.top() ==  <  && s[i] !=  > )           count++;         a.pop();       }     }     if (a.size() == 0 && flag == 0)       cout << count;     else       cout <<  Impossible ;     return 0;   }   