Submission #990547

#	Time	Username	Problem	Language	Result	Execution time	Memory
990547		ToniB	Intergalactic ship (IZhO19_xorsum)	C++17	17 / 100	2078 ms	412 KiB

xorsum

#include <bits/stdc++.h>
using namespace std;

typedef long long ll;
const int MOD = 1e9 + 7;
const int N = 105;

int n, a[N], q, l[N], r[N], x[N], pre[N], ans;

int main(){
	cin >> n;
	for (int i = 0; i < n; ++i) cin >> a[i];
	
	cin >> q;
	for (int i = 0; i < q; ++i) {
		cin >> l[i] >> r[i] >> x[i], --l[i], --r[i];
	}
	
	for (int i = 0; i < (1 << q); ++i) {
		for (int j = 0; j < q; ++j) {
			if (i & 1 << j) {
				pre[l[j]] ^= x[j];
				pre[r[j] + 1] ^= x[j];
			}
		}
		for (int i = 1; i < n; ++i) pre[i] ^= pre[i - 1];
		for (int i = 0; i < n; ++i) a[i] ^= pre[i];

		int sum = 0;
		for (int i = 0; i < n; ++i) {
			int cur = 0;
			for (int j = i; j < n; ++j) {
				cur += a[j];
				sum += cur * cur;
				sum %= MOD;
			}
		}
		ans += sum;
		ans %= MOD;

		for (int i = 0; i < n; ++i) {
			a[i] ^= pre[i];
			pre[i] = 0;
		}
	}
	
	cout << ans << "\n";
	
	return 0;
}

• Subtask 1: 4 / 4
• Subtask 2: 5 / 5
• Subtask 3: 0 / 6
• Subtask 4: 0 / 9
• Subtask 5: 8 / 8
• Subtask 6: 0 / 11
• Subtask 7: 0 / 19
• Subtask 8: 0 / 30
• Subtask 9: 0 / 8