#include <bits/stdc++.h>

using namespace std;

bool evaluate( const size_t & redCount, const size_t & blueCount ){
    if( blueCount < redCount ){
        double temp = sqrt( blueCount );
        if( floor( temp ) != temp ){
            return false;
        }
        return true;
    }
    else{
        double temp = sqrt( redCount );
        if( floor( temp ) != temp){
            return false;
        }
        return true;
    }
}

signed main()
{
    ios::sync_with_stdio(0); cin.tie(0); cout.tie(0);

    vector<bool> tiles;
    size_t n;
    cin >> n;

    char temp;

    size_t blueTiles = 0;
    size_t redTiles = 0;
    size_t res = 0;

    while(n--){
        cin >> temp;
        if( temp == 'X'){
            blueTiles++;
            tiles.emplace_back(true);
        }
        else{
            redTiles++;
            tiles.emplace_back(false);
        }
    }

    size_t patioTileCountMax;

    if( blueTiles < redTiles ){
        patioTileCountMax = floor( sqrt( blueTiles ) );
    }
    else{
        patioTileCountMax = floor( sqrt( redTiles ) );
    }

    patioTileCountMax += 2;
    size_t patioSide = patioTileCountMax;
    patioTileCountMax = pow( patioTileCountMax, 2);

    size_t blueCount = 0;
    size_t redCount = 0;

    while( patioSide >= 3 ){
        patioTileCountMax = pow( patioSide, 2);
        // cout << patioTileCountMax << endl;   
        if( tiles.size() < patioTileCountMax ){
            // cout << "skipped" << endl;
            patioSide--;
            continue;
        }

        size_t i = 0;
        for( ; i < patioTileCountMax; i++){
            if( tiles[ i ] == 0 ){
                blueCount++;
            }
            else{
                redCount++;
            }
        }
        if( evaluate(redCount, blueCount ) ) res++;

        i = 1;     
        while( i + patioTileCountMax - 1 < tiles.size() ){

            i++;

            if( tiles[ i + patioTileCountMax - 1 ] == true ){
                blueCount++;
            }
            else{
                redCount++;
            }

            if( tiles[i - 1] == false ){
                blueCount--;
            }
            else{
                redCount--;
            }
            if( evaluate(redCount, blueCount ) ) res++;

        }

        patioSide--;
    }

    cout << res << endl;

    return 0;
}