Given vector of tuples create two separate lists

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I have a vector of tuples:

let v = vec![(1, 1), (1, 1), (1, 3), (1, 4), (2, 2), (2, 4), (2, 6)];

and I would like to split it into two lists. The first list containing the first element from each of the tuples and the second containing the second one, i.e.:

l1 = [1, 1, 1, 1, 2, 2] and l2 = [1, 1, 3, 4, 2, 4].

How can I do this?

rust
2 Answers

Iterator.unzip() is specifically created for this. Playground

fn main() {
    let v = vec![(1, 1), (1, 1), (1, 3), (1, 4), (2, 2), (2, 4), (2, 6)];
    let (v1, v2): (Vec<_>, Vec<_>) = v.into_iter().unzip();
    println!("{:?}", v1);
    println!("{:?}", v2);

    // [1, 1, 1, 1, 2, 2, 2]
    // [1, 1, 3, 4, 2, 4, 6]
}
user_85649990

@Alexey Larionov's answer is perfect, but if you were looking for a more manual approach, it's still quite reasonable given Rust's ability to pattern match.

fn main() {
    let v = vec![(1, 1), (1, 1), (1, 3), (1, 4), (2, 2), (2, 4), (2, 6)];
    
    let mut v1: Vec<i32> = vec![];
    let mut v2: Vec<i32> = vec![];
    
    for (first, second) in v {
        v1.push(first);
        v2.push(second);
    }
    
    println!("{:?}", v1);
    println!("{:?}", v2);
}
user_152613150
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