>>> from cerca import cerca_suma

--ini-enunciat

>>> it = iter([1, 2, 3, 4, 10, 20, -5, 35, 88])
>>> it2 = cerca_suma(it)
>>> next(it2)
3
>>> for v in it2:
...    print(v, end=",")
10,20,35,

--fi-enunciat

>>> for v in cerca_suma(iter([0, 1, 1, 2, 4, 8, 16, 32, 64, 100])):
...    print(v, end=",")
0,1,2,4,8,16,32,64,

>>> for v in cerca_suma(iter([1, -1, 0] * 10)):
...    print(v, end=",")
0,0,0,0,0,0,0,0,0,0,

>>> for v in cerca_suma(iter(range(100))):
...    print(v, end=",")
0,3,

>>> for v in cerca_suma(iter([1,-2,4])):
...    print(v, end=",")