1package foo
2
3func f(m, n int) int {
4	a := g(n)
5	b := g(m)
6	return a + b
7}
8
9func g(x int) int {
10	y := h(x + 1)
11	z := h(x - 1)
12	return y + z
13}
14
15func h(x int) int {
16	return x * x
17}
18