public class maxsubarraysum {

    public static void main(String[] args) {
        int numbers[] = { 1, -2, 6, -1, 3 };
        printmsasum(numbers);
    }

    public static void printmsasum(int numbers[]) {
        int currsum=0;//declared and initialized
        int maxsum = Integer.MIN_VALUE;
        for (int i = 0; i < numbers.length; i++) {
            int start = i;
            for (int j = i; j < numbers.length; j++) {
                int end = j;
                 currsum = 0;                    //here is what i dont understand why i have to again give it zero to run it properly what its is called ? means am i missing any concept? pls help in loops does value changes?
                for (int k = start; k <= end; k++) {
                    currsum += numbers[k];
                }
                System.out.println(currsum);
                if (maxsum < currsum) {
                    maxsum = currsum;
                }
            }
        }
        System.out.println("the maximum sub array sum is = " + maxsum);
    }

}

我试过只声明和用零初始化currsum变量，然后输出是错误的，然后在第二个嵌套循环中，为什么我必须用零初始化它才能得到正确的答案？