2x2 squares

#include <iostream>
#include <vector>

std::vector<std::vector<char>> readMatrix(int& rows, int& cols) {
    std::cin >> rows >> cols;
    std::vector<std::vector<char>> matrix;
    for (int i = 0; i < rows; ++i) {
        std::vector<char> row;
        for (int j = 0; j < cols; ++j) {
            char c; std::cin >> c;
            row.push_back(c);
        }
        matrix.push_back(row);
    }
    return matrix;
}

void findSquares(std::vector<std::vector<char>>& matrix) {
    int squaresCounter = 0;

    for (int i = 0; i < matrix.size(); ++i) {
        for (int j = 0; j < matrix[i].size(); ++j) {
            if (i + 1 < matrix.size() && j + 1 < matrix[i].size()) {
                if (matrix[i][j] == matrix[i][j + 1] && matrix[i + 1][j] == matrix[i + 1][j + 1] && matrix[i][j] == matrix[i + 1][j]) {
                    squaresCounter++;
                }
            }
        }
    }
    std::cout << squaresCounter;
}

int main() {
    int rows, cols;
    std::vector<std::vector<char>> matrix = readMatrix(rows, cols);
    findSquares(matrix);
}