fn main() {
let m = 3
let n = 3
println(ackermann(m, n))
}
fn ackermann(m: int, n: int): int {
if m == 0 {
return n + 1
} else if n == 0 {
return ackermann(m - 1, 1)
} else {
return ackermann(m - 1, ackermann(m, n - 1))