function [BOOL] = chk_Euler_rule(V, F)
    V_n = size(V, 1);
    F_n = size(F, 2);
    arr = zeros(V_n, V_n);

    for i = 1 : F_n
        a = F(1, i);
        b = F(2, i);
        c = F(3, i);

        if a < b
            arr(a,b) = 1;
        else
            arr(b,a) = 1;
        end

        if a < c
            arr(a,c) = 1;
        else
            arr(c,a) = 1;
        end

        if b < c
            arr(b,c) = 1;
        else
            arr(c,b) = 1;
        end
    end

    E_n = sum(arr(:) == 1);
    expected = V_n + F_n -2
    actual = E_n
    BOOL = expected == actual;