(4 votes, average: 3.50 out of 5)Now the difficulties are : if the dog is left with anyone and the maid isn’t there to control him, he’ll bite. The dad can’t be left with any of the daughters when the mom isn’t there. Likewise, the mom can’t be trusted alone with either of the sons when the dad isn’t there.
Remember! only an adult can operate the boat, and the boat can’t drive itself.See Solution : River crossing - the harder one
Say
West shore is {W} and East shore is {E}
Lets give the nick names to each family member and dog 😉
Mother – {m}, Father – {F}, Daughters – {d1, d2}, Sons – {s1, s2}
House maid – {h}, Dog – {d}
Initially,
W = {m, d1, d2, f, s1, s2, h, d}
E = {…}
let’s move everyone, over…
housemaid and dog go east, and the housemaid comes back:
W = {m, d1, d2, f, s1, s2, h}
E = {d}
housemaid and s1 go east, h and d come back:
W = {m, d1, d2, f, s2, h, d}
E = {s1}
father and s2 go east, father comes back:
W = {m, d1, d2, f, h, d}
E = {s1, s2}
mother and father go east, mother comes back:
W = {m, d1, d2, h, d}
E = {f, s1, s2}
h and d go east, father comes back:
W = {m, d1, d2, f}
E = {s1, s2, h, d}
father and mother go east, mother comes back:
W = {m, d1, d2}
E = {f, s1, s2, h, d}
mother and d1 go east, housemaid and d come back:
W = {d2, h, d}
E = {m, d1, f, s1, s2}
h and d2 go east, h comes back
W = {h, d}
E = {m, d1, d2, f, s1, s2}
h and d go east
W = {}
E = {m, d1, d2, f, s1, s2, h, d}
And we are done.
