class Solution {
    public int largestSumAfterKNegations(int[] A, int K) {
        if (A.length == 1) return k % 2 == 0 ? A[0] : -A[0];
        Arrays.sort(A);
        int sum = 0;
        int idx = 0;
        for (int i = 0; i < K; i++) {
            if (i < A.length - 1 && A[idx] < 0) {
                A[idx] = -A[idx];
                if (A[idx] >= Math.abs(A[idx + 1])) idx++;
                continue;
            }
            A[idx] = -A[idx];
        }

        for (int i = 0; i < A.length; i++) {
            sum += A[i];
        }
        return sum;
    }
}

class Solution {
    public int canCompleteCircuit(int[] gas, int[] cost) {
        int curSum = 0;
        int totalSum = 0;
        int index = 0;
        for (int i = 0; i < gas.length; i++) {
            curSum += gas[i] - cost[i];
            totalSum += gas[i] - cost[i];
            if (curSum < 0) {
                index = (i + 1) % gas.length ; 
                curSum = 0;
            }
        }
        if (totalSum < 0) return -1;
        return index;
    }
}

class Solution {
    public int candy(int[] ratings) {
        int len = ratings.length;
        int[] candyVec = new int[len];
        candyVec[0] = 1;
        for (int i = 1; i < len; i++) {
            candyVec[i] = (ratings[i] > ratings[i - 1]) ? candyVec[i - 1] + 1 : 1;
        }

        for (int i = len - 2; i >= 0; i--) {
            if (ratings[i] > ratings[i + 1]) {
                candyVec[i] = Math.max(candyVec[i], candyVec[i + 1] + 1);
            }
        }

        int ans = 0;
        for (int num : candyVec) {
            ans += num;
        }
        return ans;
    }
}