Play Nim (and loose) against computer (« Je peux perdre, mais je gagne toujours. »).
This toy program aims at implementing the ever winning algorithm (described at https://en.wikipedia.org/wiki/Nim#Mathematical_theory and https://en.wikipedia.org/wiki/Nim#Proof_of_the_winning_formula).
Type make nim to create the executable, then ./nim.
Here is a sample of an interactive game between the human player ("you") and the computer ("I").
16 elements are gathered into 4 heaps:
Heap 1: | [1 element(s)]
Heap 2: | | | [3 element(s)]
Heap 3: | | | | | [5 element(s)]
Heap 4: | | | | | | | [7 element(s)]
Each player (you and I) alternate taking any number of elements from any single one of the 4 heaps.
The loser is the one taking the last element.
Do you want to play first ([y]es/no) ? y
> Your turn.
Choose a heap to remove elements from: 1
Removing 1 element(s) from heap 1:
Heap 2: | | | [3 element(s)]
Heap 3: | | | | | [5 element(s)]
Heap 4: | | | | | | | [7 element(s)]
> My turn.
Humm, i'm thinking...
OK, let me play.
Removing 1 element(s) from heap 4:
Heap 2: | | | [3 element(s)]
Heap 3: | | | | | [5 element(s)]
Heap 4: | | | | | | [6 element(s)]
> Your turn.
Choose a heap to remove elements from: 4
Choose the number of elements to remove from heap 4 (out of 6): 2
Removing 2 element(s) from heap 4:
Heap 2: | | | [3 element(s)]
Heap 3: | | | | | [5 element(s)]
Heap 4: | | | | [4 element(s)]
> My turn.
Humm, i'm thinking...
OK, let me play.
Removing 2 element(s) from heap 2:
Heap 2: | [1 element(s)]
Heap 3: | | | | | [5 element(s)]
Heap 4: | | | | [4 element(s)]
> Your turn.
Choose a heap to remove elements from: 2
Removing 1 element(s) from heap 2:
Heap 3: | | | | | [5 element(s)]
Heap 4: | | | | [4 element(s)]
> My turn.
Humm, i'm thinking...
OK, let me play.
Removing 1 element(s) from heap 3:
Heap 3: | | | | [4 element(s)]
Heap 4: | | | | [4 element(s)]
> Your turn.
Choose a heap to remove elements from: 3
Choose the number of elements to remove from heap 3 (out of 4): 2
Removing 2 element(s) from heap 3:
Heap 3: | | [2 element(s)]
Heap 4: | | | | [4 element(s)]
> My turn.
Humm, i'm thinking...
OK, let me play.
Removing 2 element(s) from heap 4:
Heap 3: | | [2 element(s)]
Heap 4: | | [2 element(s)]
> Your turn.
Choose a heap to remove elements from: 3
Choose the number of elements to remove from heap 3 (out of 2): 1
Removing 1 element(s) from heap 3:
Heap 3: | [1 element(s)]
Heap 4: | | [2 element(s)]
> My turn.
Humm, i'm thinking...
OK, let me play.
Removing 2 element(s) from heap 4:
Heap 3: | [1 element(s)]
> Your turn.
Choose a heap to remove elements from: 3
Removing 1 element(s) from heap 3:
No more heaps.
You loose (« Je peux perdre, mais je gagne toujours »).