package cap3

// Ex2 例2 求1000以内的完数，返回一个map，key为完数，value为其因数的数组
func Ex2() map[int][]int {
    result := map[int][]int{}
    for i := range 1000 {
        if i < 2 {
            continue
        }

        sum := 0
        factors := make([]int, 0, 20)
        for j := 1; j <= i/2; j++ {
            if i%j == 0 {
                factors = append(factors, j)
                sum += j
            }
        }

        if sum == i {
            result[i] = factors
        }
    }

    return result
}