GFG PTOD | 16 Jan 2025 | Largest subarray of 0’s and 1’s

int maxLen(vector<int> &arr) {
        // Your code here
        int res=0, sum=0;
        unordered_map<int, int> mp;
        
        for(int i=0; i<arr.size(); i++) {
            sum += (arr[i] == 0) ? -1 : 1;
            if(sum == 0) res = max(res, i+1);
            else if(mp.find(sum) != mp.end()) res = max(res, i-mp[sum]);
            else mp[sum] = i;
        }
        
        return res;
    }