977. 有序数组的平方

977. 有序数组的平方

提示：

1. 1 <= A.length <= 10000
2. -10000 <= A[i] <= 10000
3. A 已按非递减顺序排序。

排序

func sortedSquares(A []int) []int {
    for i,v:=range A{
        A[i] = v*v
    }
    sort.Ints(A)
    return A
}

双指针

package main
import (
    "fmt"
)
func sortedSquares(A []int) []int {
    res := make([]int, len(A))
    l := 0
    r := len(A) - 1
    i := len(res) - 1
    var lRes, rRes int
    for l <= r {
        lRes = A[l] * A[l]
        rRes = A[r] * A[r]
        if lRes > rRes {
            res[i] = lRes
            l++
        } else {
            res[i] = rRes
            r--
        }
        i--
    }
    return res
}
func main() {
    fmt.Println(sortedSquares([]int{-4,-1,0,3,10}))
    fmt.Println(sortedSquares([]int{-7, -3, 2, 3, 11}))
    fmt.Println(sortedSquares([]int{1}))
}