# Number Theory: Problem 1

### Correct solution

x |
y |
r |

6409 |
42823 |
6409 |

42823 |
6409 |
4369 |

6409 |
4369 |
2040 |

4369 |
2040 |
289 |

2040 |
289 |
17 |

289 |
17 |
0 |

17 |
0 |
N/A |

The return value is 17.

### Self-check

Did you explicitly show the output value? It's easy to lose points on exams by
not following instructions like this one.

If your table had a lot more steps, were you subtracting off the smaller number
rather than taking the remainder?

Did you start with the numbers in the order given, i.e. so the first iteration
swaps the values of x and y?

The last line is technically necessary, because the main variables are reset before
the loop halts. If a picky person is grading your solution, they might take off
points for not including it.