#include <iostream>
#include <map>
#include <vector>
using namespace std;

int main(int argc, char **argv)
{
    char array[7] = {'A', 'A', 'B', 'B', 'A', 'G', 'A'}; 
    map<char, int> letter_count;
    for(int i = 0; i < 7; ++i)
    {
        ++letter_count[array[i]];
    }
    map<char, int>::iterator iter;
    int repeat_letter_count = 0;
    for(iter = letter_count.begin(); iter != letter_count.end(); ++iter)
    {
        repeat_letter_count += (*iter).second - 1;
    }
    cout << "Number of repeated letters: " << repeat_letter_count << endl;
    
    return 0;
}