1 //New presum 2 class Solution { 3     public boolean checkSubarraySum(int[] nums, int k) { 4         if(k == 0){ 5             for(int i = 1; i < nums.length; i++){ 6                 if(nums[i] == 0 && nums[i-1] == 0) return true; 7             } 8             return false; 9         }10         int[] presum = new int[nums.length + 1];11         for(int i = 0; i < nums.length; i++){12             presum[i+1] = presum[i] + nums[i];13         }14         for(int i = 0; i <= nums.length-2; i++){15             for(int j = i+2; j <= nums.length; j++){16                 if((presum[j] - presum[i]) % k == 0){17                     return true;18                 }19             }20         }21         return false;22         23     }24 }25 26 //Old27 class Solution {28     public boolean checkSubarraySum(int[] nums, int k) {29         30         List
     
       list = new ArrayList<>();31         for(int i = 0; i < nums.length; i++){32             for(int j = 0; j < list.size(); j++){33                 // System.out.println(list.get(j) + nums[i]);34                 if((k == 0 && list.get(j) + nums[i] == 0) || (k != 0 && (list.get(j) + nums[i]) % k == 0)){35                     return true;36                 }else{37                     list.set(j, list.get(j) + nums[i]);38                 }39             }40             list.add(nums[i]);41         }42         return false;43         44     }45 }