original.name="For_Valid_2"
======
>>> main.whiley
public function sum(int[][] items) -> int:
int r = 0
for i in 0..|items|:
int[] ith = items[i]
for j in 0..|ith|:
r = r + ith[j]
// Done
return r
public export method test():
assume sum([[1]]) == 1
assume sum([[1,2]]) == 3
assume sum([[1,2],[3]]) == 6
assume sum([[1,2],[3],[4,5,6]]) == 21
---