30 Days of Code [Day 17]

30 Aug 2021

QUESTION : 1310. XOR Queries of a Subarray

#define vi vector<int>
#define pii pair<int, int>
#define pb push_back
#define mp make_pair
#define all(v) v.begin(), v.end()
#define fo(i,s,n) for(int i=s;i<n;++i)
#define of(i,s,n) for(int i=s-1;i>=n;--i)
#define fv(V) for( auto &it : V )
#define fastio ios_base::sync_with_stdio(0); cin.tie(0); cout.tie(0);
class Solution {
public:
    vector<int> xorQueries(vector<int>& arr, vector<vector<int>>& queries) {
        fastio;
        int n = arr.size();
        vi res;
        res.reserve(queries.size());
        fo(i,1,n){
            arr[i] = (arr[i-1] ^ arr[i]);
        }
        fv(queries){
            if(!it[0])
                res.pb(arr[it[1]]);
            else res.pb(arr[it[0]-1] ^ arr[it[1]]);
        }
        return res;
    }
};