feat: add java solution to lc problem: No.1304

[0xcaffebabe]

No description provided.

[yanglbme]

Hi @0xcaffebabe , I think the following code would be better :D

class Solution {
    public int[] sumZero(int n) {
        int preSum = 0;
        int[] ret = new int[n];
        for (int i = 1; i < n; ++i) {
            ret[i - 1] = i;
            preSum += i;
        }
        ret[n - 1] = -preSum;
        return ret;
    }
}