Leetcode977:有序数组的平方——双指针

class Solution {
public:
    vector<int> sortedSquares(vector<int>& nums) {
        for(int i=0;i<nums.size();i++){
            nums[i] = nums[i]*nums[i];
        }
        sort(nums.begin(),nums.end());
        return nums;

    }
};

class Solution {
public:
    vector<int> sortedSquares(vector<int>& nums) {
        int i = 0;
        int j = nums.size()-1;
        int k = j;
        vector<int> res(nums.size());
        while(i<=j){
            if(nums[i]*nums[i] <= nums[j]*nums[j]){
                res[k--] = nums[j]*nums[j];
                j--;
            }else{
                res[k--] = nums[i]*nums[i];
                i++;
            }
        }
    return res;
    }
};