1. Two Sum

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🚀 Approach 1: Sorting (Most Intuitive)

https://leetcode.com/problems/two-sum-ii-input-array-is-sorted/

Space - O(1)
 
 
If Array - Sorted
	TC - n
else 
	TC - nlog(n)

class Solution {
public:
	vector<int> twoSum(vector<int>& arr, int target) {
		int s = 0, e = arr.size() - 1;
		while (s < e)
		{
			int sum = arr[s] + arr[e];
			if (sum > target) e--;
			else if (sum < target) s++;
			else return {s + 1, e + 1};
		}
		return { -1, -1};
	}
};

🚀 Approach 2: #  Frequency Count (Optimal)

https://leetcode.com/problems/two-sum/description/

Space - O(n)
 
If Array - Sorted
	TC - n
else 
	TC - nlog(n)

class Solution {
public:
    vector<vector<string>> groupAnagrams(vector<string>& strs) {
        map<vector<int> ,vector<string>> um;
        vector<vector<string>> ans;
 
        for(auto &&i: strs)
        {
            vector<int> freq(26);
            for(auto &&j: i)
                freq[j-'a']++;
            um[freq].push_back(i);
        }
 
        for(auto i: um) ans.push_back(i.second);
        return ans;
    }
};

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