Interview Cake Weekly Problem #232: Parenthesis Matching

paranthesis_matching.hpp

/*
I like parentheticals (a lot).

"Sometimes (when I nest them (my parentheticals) too much (like this (and this))) they get confusing."

Write a function that, given a sentence like the one above, along with the position of an opening parenthesis, finds the corresponding closing parenthesis.

Example: if the example string above is input with the number 10 (position of the first parenthesis), the output should be 79 (position of the last parenthesis).
*/

#include <iostream>
#include <string>
#include <map>
#include <stack>

int find_corresponding_end_paranthesis(std::string text, int open_paranthesis_index){
  std::map<int, int> paranthesis;
  std::stack<int> history;

  for(int i=open_paranthesis_index; i<text.size();++i){
    if(text[i]==')'){
      int openIndex = history.top();
      history.pop();
      paranthesis.emplace(openIndex, i);
    }else if(text[i]=='('){
      history.push(i);
    }
  }
  return paranthesis[open_paranthesis_index];
}


int main() {
  
  std::string text = "Sometimes (when I nest them (my parentheticals) too much (like this (and this))) they get confusing.";
  
  std::cout<<find_corresponding_end_paranthesis(text, 10)<<std::endl;

  return 0;
}