博客

前缀和

class Solution {
    public int maxAbsoluteSum(int[] nums) {
       //前缀和
        int positiveSum = 0,positiveMax = 0,negativeSum = 0,negativeMin = 0;
        for(int i = 0; i < nums.length; i++){
            positiveSum += nums[i];
            positiveMax = Math.max(positiveSum,positiveMax);
            //如果加上当前数字和小于0，那么变为0从新开始，如果还大于0那么就继续相加。
            positiveSum = Math.max(0,positiveSum);
            negativeSum += nums[i];
            negativeMin = Math.min(negativeSum,negativeMin);
            negativeSum = Math.min(0,negativeSum);
        }
        return Math.max(positiveMax,-negativeMin);
    }
}