# Population Simulation

## Objective

To be able to write simulation programs.

## Task

Google used to use an interview question that tested candidates statistics
and reasoning skills. The questions goes like this:

In a country in which people only want boys, every family continues to have
children until they have a boy. If they have a girl, they have another child.
If they have a boy, they stop. What is the proportion of boys to girls in the country?

Before beginning to solve this problem, make a guess as to what the answer is,
put this guess in the comments of your program before writing it.

## Simulation

We could solve this problem using statistics, but we can also simulate this
hypothetical country and empirically see what will happen.

- Create a class called "Family" which contains two private variables: one for the
number of boys, and one for the number of girls.
- Create a constructor which sets both to 0.
- Create "getter" functions which return the number of boys and girls.
- Create a function called "step" which will simulate one cycle of the family.
If the family already has a boy, the function returns right away. If the family does
not have a boy, they have a child. Use a random number generator to decide if
they have a boy or girl (it should be 50/50 of course).
- In the main function, create and initialize an array of one million families.
- Call the "step" function on each until every family has a boy.
- Print the number of boys, the number of girls, and the percentage of the population
which is male.

## Submitting

When your program works, email the code to ifinlay@umw.edu.
Include your conclusion in the body of the email. What is the proportion of boys
to girls in this country?
Copyright © 2019 Ian Finlayson | Licensed under a Creative Commons Attribution 4.0 International License.