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  • My Approach
  • Time and Auxiliary Space Complexity
  • Code (C++)
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  1. 10-October

03. Number of Good Pairs

Previous02. Remove Colored Pieces if Both Neighbors are the Same ColorNext04. Design HashMap

Last updated 1 year ago

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The problem can be found at the following link:

My Approach

  1. Initialize an unordered map of int.

  2. Iterate through the given values in the array. For each piece in the iteration:

    • Check if the current value is present in the map or not If yes, increment count as it is a valid pair.

    • If it is not present in the map then insert the value in the map

  3. Return count which stores the count of all valid pairs .

Time and Auxiliary Space Complexity

  • Time Complexity: O(n)

  • Auxiliary Space Complexity: O(n)

Code (C++)


class Solution {
public:
    int numIdenticalPairs(vector<int>& a) {
        int i,count=0;

        unordered_map<int,int>map;

        for(i=0;i<a.size();i++){
            if(map.find(a[i])!=map.end())
            count +=map[a[i]];
                
            map[a[i]]++;
        }
        return count;
    }
};

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rishabhv12/Daily-Leetcode-Solution