// Checking symbol shadowing
func shadow() begin
    var a, b
    a := 1
    begin
        var a
        a := 2
        b := 40
        begin
            var a
            a := b + 2
            print a, b
        end
        print a
        begin
            var b
            b := 38
            a := b + 3
            print a, b
        end
        print a
    end
    print b
    return 0
end