Submission #596772

#	Time	Username	Problem	Language	Result	Execution time	Memory
596772		Cookie	XORanges (eJOI19_xoranges)	C++14	100 / 100	177 ms	16116 KiB

xoranges

#include<bits/stdc++.h>
using namespace std;
#define ll long long
#define vt vector
#define pb push_back
const int mxn = 2e5 + 3;
ll a[mxn];
int n, q;
ll odd[mxn * 4] = {}, even[mxn * 4] = {};
void build(int nd, int l, int r){
    if(l == r){
        if(l % 2 == 0)even[nd] = a[l];
        else odd[nd] = a[l];
        return;
    }
    int mid = (l + r) >> 1;
    build((nd << 1), l, mid); build((nd << 1) + 1, mid + 1, r);
    odd[nd] = odd[(nd << 1)] ^ odd[(nd << 1) + 1]; even[nd] = even[(nd << 1)] ^ even[(nd << 1) + 1];
}
void upd(int nd, int l, int r, int id, ll v){
    if(id > r || id < l)return;
    if(l == r){
        even[nd] = v;
        return;
    }
    int mid = (l + r) >> 1;
    upd((nd << 1), l, mid, id, v); upd((nd << 1) + 1, mid + 1, r, id, v);
     even[nd] = even[(nd << 1)] ^ even[(nd << 1) + 1];
}
void upd2(int nd, int l, int r, int id, ll v){
    if(id > r || id < l)return;
    if(l == r){
        odd[nd] = v;
        return;
    }
    int mid = (l + r) >> 1;
    upd2((nd << 1), l, mid, id, v); upd2((nd << 1) + 1, mid + 1, r, id, v);
     odd[nd] = odd[(nd << 1)] ^ odd[(nd << 1) + 1];
}
ll get(int nd, int l, int r, int ql, int qr){
    if(ql > r || qr < l)return(0);
    if(ql <= l && qr >= r)return(even[nd]);
    int mid = (l + r) >> 1;
    return(get((nd << 1), l, mid, ql, qr) ^ get((nd << 1) + 1, mid + 1, r, ql,qr));
}
ll get2(int nd, int l, int r, int ql, int qr){
    if(ql > r || qr < l)return(0);
    if(ql <= l && qr >= r)return(odd[nd]);
    int mid = (l + r) >> 1;
    return(get2((nd << 1), l, mid, ql, qr) ^ get2((nd << 1) + 1, mid + 1, r, ql,qr));
}
int main(){
	ios_base::sync_with_stdio(0); cin.tie(0); cout.tie(0);
	cin >> n >> q;
	for(int i = 1; i <= n; i++)cin >> a[i];
    build(1, 1, n);
	for(int i = 0; i < q; i++){
	    int qq; cin >> qq;
	    if(qq == 1){
	        int id; cin >> id; ll x; cin >> x;
	        if(id % 2 == 0){
	            upd(1, 1, n, id, x);
	        }else{
	            upd2(1, 1, n, id, x);
	        }
	        a[id] = x;
	    }else{
	        int l, r; cin >> l >> r;
	        if((r - l + 1) % 2 == 0)cout << 0 << "\n";
	        else{
	            if(l % 2 == 0){
	                cout << get(1, 1, n, l, r) << "\n";
	            }else{
	                cout << get2(1, 1, n, l, r) << "\n";
	            }
	        }
	    }
	}
}

• Subtask 1: 12 / 12
• Subtask 2: 18 / 18
• Subtask 3: 25 / 25
• Subtask 4: 20 / 20
• Subtask 5: 25 / 25