Submission #464031

#	Time	Username	Problem	Language	Result	Execution time	Memory
464031		Alen777	XORanges (eJOI19_xoranges)	C++14	55 / 100	726 ms	2380 KiB

xoranges

#include <iostream>
#include <string>
#include <iomanip>
#include <vector>
#include <set>
#include <map>
#include <queue>
#include <stack>
#include <cmath>
#include <algorithm>
#include <cstring>
using namespace std;

#define ll long long
#define ull unsigned ll
#define pb push_back
#define mpr make_pair
#define lb lower_bound
#define ld long double
#define ub upper_bound

const int N = 100002;

int a[N];
ll t[4 * N];

void build(int tl, int tr, int v) {
	if (tl == tr) {
		t[v] = a[tl];
	}
	else {
		int m = (tl + tr) / 2;
		build(tl, m, v * 2);
		build(m + 1, tr, v * 2 + 1);
		t[v] = t[v * 2] ^ t[v * 2 + 1];
	}
}

ll sum(int tl, int tr, int l, int r, int v) {
	if (l > r)
		return 0;
	if (l == tl && r == tr)
		return t[v];
	int m = (tl + tr) / 2;
	return sum(tl, m, l, min(r, m), v * 2)
		^ sum(m + 1, tr, max(l, m + 1), r, v * 2 + 1);
}

void update(int tl, int tr, int v, int pos, int new_val) {
	if (tl == tr) {
		t[v] = new_val;
	}
	else {
		int m = (tl + tr) / 2;
		if (pos <= m) {
			update(tl, m, v * 2, pos, new_val);
		}
		else {
			update(m + 1, tr, v * 2 + 1, pos, new_val);
		}
		t[v] = t[v * 2] ^ t[v * 2 + 1];
	}
}

void solve() {
	int n, q;
	cin >> n >> q;
	for (int i = 1; i <= n; i++) {
		cin >> a[i];
	}
	build(1, n, 1);
	for (int i = 1; i <= q; i++) {
		int c, l, r;
		cin >> c >> l >> r;
		if (c == 1) {
			update(1, n, 1, l, r);
		}
		else {
			if (r - l + 1 == 2) {
				cout << 0 << endl;
			}
			else if (r - l + 1 == 1) {
				cout << sum(1, n, l, r, 1) << endl;
			}
			else {
				ll ans = 0;
				if ((r - l + 1) % 2 == 0) {
					cout << 0 << endl;
				}
				else {
					for (int i = l; i <= r; i++) {
						if (i % 2 == l % 2) {
							ans ^= sum(1, n, i, i, 1);
						}
					}
					cout << ans << endl;
				}
			}
		}
	}
}

int main() {
    /*cout.setf(ios::fixed | ios::showpoint);
    cout.precision(6);*/
    ios_base::sync_with_stdio(false); cin.tie(0); cout.tie(0);
    solve();
    return 0;
}

• Subtask 1: 12 / 12
• Subtask 2: 18 / 18
• Subtask 3: 25 / 25
• Subtask 4: 0 / 20
• Subtask 5: 0 / 25