2295_ReplaceElementsinanArray - a920604a/leetcode GitHub Wiki

class Solution {
public:
    vector<int> arrayChange(vector<int>& nums, vector<vector<int>>& operations) {
        unordered_map<int,int> mp;
        int n = nums.size();
        for(int i=0;i<n;++i) mp[nums[i]] = i;
        for( auto op : operations){
            nums[mp[op[0]]] = op[1];
            mp[op[1]] = mp[op[0]];
            mp.erase(op[0]); // option
        }
        return nums;
    }
};