# Problem-Solving Skills

#### Quirk

##### Distinguished Member
I'm sure there are some people here who know a lot about problem solving strategies. I got this from a friend via email the other day:

"Everybody has to cross the river".
http://freeweb.siol.net/danej/riverIQGame.swf
(To start, click on the big blue circle on the right.)

The following rules apply:

• Only 2 persons can travel on the raft at a time

• The father can not stay with any of the daughters without their mother's presence

• The mother can not stay with any of the sons without their father's presence

• The thief (striped shirt) can not stay with any family member if the Policeman is not there

• Only the Father, the Mother and the Policeman know how to operate the raft

• To move the people, click on them; to move the raft, click on the pole on the opposite side of the river.
A friend of mine showed me the solution quickly, but I wan't able to figure out what the key is to solving the puzzle. Is it like the nine-dots puzzle, where there's some mental block/unrecognized assumption that you have to let go of?

#### Margaret

##### Distinguished Member
I suck at these -- anyone figure it out?

#### Mike C.

##### Distinguished Member
Scroll over solution if you want to see it...

The trick is making return trips with strategic pairs and making trips with unlikely combos. The mom and dad can travel together. The policeman can escort the second to last person leaving the theif alone on one side. The policeman can then return alone to pick up the theif.

#### DNW

##### Stylish Dinosaur
Arrrgh...I've just solved it but I didn't write down the steps.

The key is the policeman, who can be used to bring people over without violating the rule. Anytime you get stuck, think about what you can do with the policeman.

#### designprofessor

##### Distinguished Member
Originally Posted by DarkNWorn
Arrrgh...I've just solved it but I didn't write down the steps.

The key is the policeman, who can be used to bring people over without violating the rule. Anytime you get stuck, think about what you can do with the policeman.

Taken away from the context of the puzzle, this is also a valuable tip!

#### Rome

##### Mr. Chocolates Godiva
I got them all across, then they all started to salute Hitler. How weird...