typ i = int
typ c = char
typ b = bool

var g1 : i
var g2 : i

fun ext(a : i, bb : i) : i

fun helper(x : i) : b =
    x == 0

fun fib(n : i) : i =
    if n == 0 then
        0
    else
        if n == 1 then
            1
        else
            fib(n - 1) + fib(n - 2)
        end
    end

fun main() : i =
    let
        var local1 : i
        var local2 : i
        typ li = i
        fun inner(a : li, bb : li) : li =
            let
                var tmp : li
            in
                tmp = a + bb,
                tmp * 2
            end
    in
        g1 = 10,
        g2 = 20,
        local1 = fib(g1),
        local2 = inner(g1, g2),
        let
            var shadow : b
            var g1 : b
        in
            shadow = helper(local1),
            g1 = shadow and true or false,
            let
                var deep : i
            in
                deep = ext(local1, local2),
                if helper(deep) then
                    g2 = deep + 1
                else
                    g2 = deep - 1
                end,
                while g2 > 0 do
                    if g2 % 2 == 0 then
                        g2 = g2 - 1
                    else
                        g2 = g2 * 2 - 3
                    end
                end,
                deep
            end
        end
    end