Merkkijonot

input/code.cpp: In function 'bool areHarmonic(std::__cxx11::string, std::__cxx11::string)':
input/code.cpp:10:20: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
  for (int i = 0; i < s1.length(); i++)
                  ~~^~~~~~~~~~~~~
input/code.cpp:12:25: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
   for (int j = i + 1; j < s1.length(); j++)
                       ~~^~~~~~~~~~~~~

#include<iostream>
#include<vector>
#include<string>

bool areHarmonic(std::string s1, std::string s2)
{
	if (s1.length() != s2.length())
		return false;

	for (int i = 0; i < s1.length(); i++)
	{
		for (int j = i + 1; j < s1.length(); j++)
		{
			if ((s1[i] == s1[j]) != (s2[i] == s2[j]))
				return false;
		}
	}

	return true;
}

int main()
{
	int n;
	std::cin >> n;

	std::vector<std::string> v;
	for (int i = 0; i < n; i++)
	{
		v.push_back(std::string());
		std::cin >> v.back();
	}

	int count = 0;

	for (int i = 0; i < n; i++)
	{
		for (int j = i+1; j < n; j++)
		{
			count += areHarmonic(v[i], v[j]);
		}
	}

	std::cout << count;

	return 0;
}