>>> from produccions import previsio_lots

---- inici

>>> u = previsio_lots(100, 80, 30, 70, 5)
>>> u
2
>>> u = previsio_lots(100, 45, 30, 70, 6)
>>> u
3
>>> u = previsio_lots(100, 20, 30, 70, 10)
>>> u
0

---- fi

>>> u = previsio_lots(100, 80, 35, 70, 20)
>>> u
1

>>> u = previsio_lots(100, 40, 30, 70, 2)
>>> u
5

>>> u = previsio_lots(0, 40, 30, 70, 20)
>>> u
4

>>> u = previsio_lots(50, 0, 30, 70, 1)
>>> u
20