Programming Practice: Finding supermajority character in a string

supermajority.c

#include <iostream>

char findSuperMajority(const std::string &str)
{
  const size_t len(str.length());
  int count(0);
  char val(str[0]);

  for (char c : str) {
    if (count == 0) {
      val = c;
      count = 1;
    } else if (val == c) {
      count++;
    } else {
      count--;
    }
  }

  count = 0;
  for (char c : str) {
    if (c == val) {
      count++;
    }
  }

  if (count <= len / 2) {
    return 0;
  }

  return val;
}

int main()
{
  std::string inputString;
  while (std::cin >> inputString) {
    char superMajority = findSuperMajority(inputString);
    if (superMajority != 0) {
      std::cout << "Super Majority: " << superMajority << std::endl;
    } else {
      std::cout << "Super Majority NOT FOUND" << std::endl;
    }
  }
  return 0;
}