辗转相除法求最大公约数

Birdcatcher Esmar and his wife Johanna face eviction from their farm in Gásadalur unless they have a son. Desperation sets in when Johanna gives birth to their third daughter. Pushed to the brink, Johanna is impregnated by another man, a French Captain, and gives birth to a son, known as ‘the birdcatcher’s son’. Everything seems perfect until the French Captain returns.。