Count Subarrays with Given XOR (Optimal One)

// problem url: https://www.codingninjas.com/codestudio/problems/1115652?topList=striver-sde-sheet-problems&utm_source=striver&utm_medium=website&leftPanelTab=1
// mode: Medium
// Xor-Prefix

#include <bits/stdc++.h> 
int subarraysXor(vector<int> &arr, int x)
{
	unordered_map<int, int> xorCnt;
	int newXor = 0;
	xorCnt[0] = 1;
	int cntSubArr = 0;
	for(int num: arr){
		newXor ^= num;
		if(xorCnt[(newXor^x)])
			cntSubArr += xorCnt[(newXor^x)];
		++xorCnt[newXor];
	}
	return cntSubArr;
}