Simple C++ program that calculates the compatibility percentage between two people based on their first name! Note that the percentages may vary depending on the order of the names: one person may love the other more or less than that one loves the first one!

love.cpp

#include<iostream>
#include<vector>

int main() {
  std::string nameConcat, name;
  std::vector<int> counter;

  std::cout << "First name of the 1st person (lowercase): ";
  std::cin >> nameConcat;
  nameConcat += " ama ";
  std::cout << "First name of the 2nd person (lowercase): ";
  std::cin >> name;
  nameConcat += name;

  std::cout << nameConcat << std::endl;

  for(size_t i = 0; i < nameConcat.size(); i++) {
    char current = nameConcat[i];
    if(current == ' ') continue;
    int currentCount = 0;
    for(int pos = i; pos < nameConcat.size(); pos++) {
      if(nameConcat[pos] != current) continue;
      nameConcat[pos] = ' ';
      currentCount++;
    }
    if(currentCount >= 10) counter.push_back(currentCount/10);
    counter.push_back(currentCount % 10);
  }

  int size;
  while((size = counter.size()) > 2) {
    for(std::vector<int>::iterator it = counter.begin(); it < counter.end(); it++)
      std::cout << *it << ' ';

    std::cout <<std::endl;

    std::vector<int> aux;
    int i;
    for(i = 0; i < size/2; i++) {
      int sum = counter[i] + counter[size-1-i];
      if(sum >= 10) aux.push_back(sum/10);
      aux.push_back(sum % 10);
    }
    if(size % 2 == 1) aux.push_back(counter[i]);
    counter = aux;
  }

  int result;
  if(counter.size() == 1) result = counter[0];
  else result = counter[0] * 10 + counter[1];

  std::cout << result << "%" << std::endl;

  return 0;
}