# championship

Generate championship fixtures using the round-robin tournament algorithm.

## Examples

### Even number of teams

```rust
use championship::create_tournement;

#[derive(Debug)]
#[allow(dead_code)]
struct User {
    name: String,
    age: u8,
}

fn main() {
    let list = vec![
        User {
            name: "Alice".to_string(),
            age: 20,
        },
        User {
            name: "Bob".to_string(),
            age: 21,
        },
        User {
            name: "Carol".to_string(),
            age: 22,
        },
        User {
            name: "Dan".to_string(),
            age: 23,
        },
    ];

    let res = create_tournement(&list, 2);

    println!("{:#?}", res);
    /*
        [
        [
            (
                User {
                    name: "Alice",
                    age: 20,
                },
                User {
                    name: "Bob",
                    age: 21,
                },
            ),
            (
                User {
                    name: "Carol",
                    age: 22,
                },
                User {
                    name: "Dan",
                    age: 23,
                },
            ),
        ],
        [
            (
                User {
                    name: "Bob",
                    age: 21,
                },
                User {
                    name: "Carol",
                    age: 22,
                },
            ),
            (
                User {
                    name: "Dan",
                    age: 23,
                },
                User {
                    name: "Alice",
                    age: 20,
                },
            ),
        ],
        [
            (
                User {
                    name: "Carol",
                    age: 22,
                },
                User {
                    name: "Alice",
                    age: 20,
                },
            ),
            (
                User {
                    name: "Bob",
                    age: 21,
                },
                User {
                    name: "Dan",
                    age: 23,
                },
            ),
        ],
        [
            (
                User {
                    name: "Bob",
                    age: 21,
                },
                User {
                    name: "Alice",
                    age: 20,
                },
            ),
            (
                User {
                    name: "Dan",
                    age: 23,
                },
                User {
                    name: "Carol",
                    age: 22,
                },
            ),
        ],
        [
            (
                User {
                    name: "Carol",
                    age: 22,
                },
                User {
                    name: "Bob",
                    age: 21,
                },
            ),
            (
                User {
                    name: "Alice",
                    age: 20,
                },
                User {
                    name: "Dan",
                    age: 23,
                },
            ),
        ],
        [
            (
                User {
                    name: "Alice",
                    age: 20,
                },
                User {
                    name: "Carol",
                    age: 22,
                },
            ),
            (
                User {
                    name: "Dan",
                    age: 23,
                },
                User {
                    name: "Bob",
                    age: 21,
                },
            ),
        ],
    ]
        */
}

```

### Odd number of teams

```rust
use championship::create_tournement;

fn main() {
    let list = vec![0, 1, 2, 3, 4];

    let res = create_tournement(&list, 1);

    println!("{:#?}", res);
    /*
    [
        [
            (
                0,
                3,
            ),
            (
                2,
                1,
            ),
        ],
        [
            (
                1,
                4,
            ),
            (
                3,
                2,
            ),
        ],
        [
            (
                2,
                0,
            ),
            (
                4,
                3,
            ),
        ],
        [
            (
                3,
                1,
            ),
            (
                0,
                4,
            ),
        ],
        [
            (
                4,
                2,
            ),
            (
                1,
                0,
            ),
        ],
    ]
        */
}
```