Type Here to Get Search Results !

Two sum using brutforce and hashmap leetcode solution.

0

Two sum using brutforce and hashmap leetcode solution.


Given an array of integers nums and an integer target, return indices of the two numbers such that they add up to target.

You may assume that each input would have exactly one solution, and you may not use the same element twice.

You can return the answer in any order.

 

Example 1:

Input: nums = [2,7,11,15], target = 9
Output: [0,1]
Explanation: Because nums[0] + nums[1] == 9, we return [0, 1].


Example 2:

Input: nums = [3,2,4], target = 6
Output: [1,2]
Example 3:

Input: nums = [3,3], target = 6
Output: [0,1]
 

Constraints:

2 <= nums.length <= 104
-109 <= nums[i] <= 109
-109 <= target <= 109



Java Solution :- 

class Solution {
    public int[] twoSum(int[] nums, int target) {
        
        
        
        for (int i=0; i<nums.length; i++) {
           int sum = 0;
       for (int j=i+1; j<nums.length; j++) {
           sum = nums[i] + nums[j];
         if (sum == target) {
              return new int[]{i,j};
              }
         }
     }
     return null;
    }
}










Run Code

Usin hashmap 


Map<Integer, Integer> map = new HashMap<>();
        for (int i=0; i<nums.length; i++) {
            int requiredNum = target - nums[i];
            if (map.containsKey(requiredNum)) {
                return new int[] { map.get(requiredNum), i};
            } else {
                map.put(nums[i], i);
            }            
        }
        return null;
    }
}





Tags

Post a Comment

0 Comments