[leetcode] 1005. Maximize Sum Of Array After K Negations : https://leetcode.com/problems/maximize-sum-of-array-after-k-negations/

Maximize Sum Of Array After K Negations.cpp

class Solution {
public:
    int largestSumAfterKNegations(vector<int>& A, int K) {
        sort(A.begin(), A.end());
        int answer = 0;
        int lastMinus = 1e9;
        for(int i=0;i<A.size();i++){
            if(A[i] < 0){
                if(0 < K){
                    A[i] *= -1; K--;
                    lastMinus = A[i];
                }
            } else {
                if(0 < K){
                    K %= 2;
                    if(0 < K){
                        if(lastMinus < A[i])
                            answer -= 2 * lastMinus;
                        else 
                            A[i] *= -1;
                    }
                    K = 0;
                }
            }
            answer += A[i];
        }
        return answer;
    }
};