Codesignal - alternatingSums

Several people are standing in a row and need to be divided into two teams. The first person goes into team 1, the second goes into team 2, the third goes into team 1*again, the fourth into *team 2, and so on.

You are given an array of positive integers - the weights of the people. Return an array of two integers, where the first element is the total weight of team 1, and the second element is the total weight of team 2 after the division is complete.

 

Example

For a = [50, 60, 60, 45, 70], the output should be
alternatingSums(a) = [180, 105].

 

설명

배열의 인덱스 first원소는 리턴 배열 첫번째, second원소는 리턴할 배열 2번째에 합산된 수가 들어간다

 

풀이

a 배열의 인덱스가 짝수면 리턴할 배열 0번에 합산, 홀수면 리턴할 배열 1번에 합산

func alternatingSums(a: [Int]) -> [Int] {
    var sum = [0,0]

    for i in 0 ..< a.count {
        if i % 2 == 0 {
            sum[0] += a[i]
        } else {
            sum[1] += a[i]
        }
    }

    return sum
}

리펙토링 해보기

func alternatingSums(a: [Int]) -> [Int] {
    var sum = [0,0]

    for i in 0 ..< a.count {
      sum[i%2] += a[i]
    }

    return sum
}