1640_Check_Array_Formation_Through_Concatenation

Leetcode 1640: Check Array Formation Through Concatenation
Detailed video Explanation: https://youtu.be/1Q4N98UQnuc
==========================================================


C++:
----
class Solution {
public:
    bool canFormArray(vector<int>& arr, vector<vector<int>>& pieces) {
        unordered_map<int, vector<int>> _map;
        for(auto p: pieces)
            _map.insert({p[0], p});
        
        int idx = 0;
        while(idx < arr.size()){
            if(_map.count(arr[idx])){
                auto piece = _map[arr[idx]];
                for(int p: piece){
                    if(p != arr[idx]) return false;
                    else idx++;
                }
            } else 
                return false;
        }
        return true;
    }
};



Java:
-----
class Solution {
    public boolean canFormArray(int[] arr, int[][] pieces) {
        Map<Integer, int[]> _map = new HashMap<>();
        for(int[] p: pieces)
            _map.put(p[0], p);
        
        int idx = 0;
        while(idx < arr.length){
            if(_map.containsKey(arr[idx])){
                int[] piece = _map.get(arr[idx]);
                for(int p: piece){
                    if(p != arr[idx]) return false;
                    else idx++;
                }
            } else 
                return false;
        }
        return true;
    }
}




Python3:
--------
class Solution:
    def canFormArray(self, arr: List[int], pieces: List[List[int]]) -> bool:
        _map = {}
        for p in pieces:
            _map[p[0]] = p
        
        idx = 0
        while idx < len(arr):
            if arr[idx] in _map:
                piece = _map[arr[idx]]
                for p in piece:
                    if p != arr[idx]: return False
                    else: idx += 1
            else:
                return False
        return True