제출 #1022520

#	제출 시각	아이디	문제	언어	결과	실행 시간	메모리
1022520		A_M_Namdar	XORanges (eJOI19_xoranges)	C++14	0 / 100	10 ms	5976 KiB

xoranges

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

const long long N = 1e5 + 10, SQ = 400;
long long n, q, a[N], dp[2][N];

int ans(int l, int r) {
    if ((r - l) & 1 == 0)
        return 0;
    int res = 0;
    int l1 = ((l + SQ - 1) / SQ) & SQ, r1 = (r / SQ) * SQ;
    if (r1 > l1) {
        for (int i = l; i < l1; i += 2)
            res ^= a[i];
        for (int i = l1; i < r1; i++)
            res ^= dp[l & 1][i];
        for (int i = r1 + (l & 1); i < r; i += 2)
            res ^= a[i];
    }
    else
        for (int i = l; i < r; i += 2)
            res ^= a[i];
    return res;
}

void input() {
    cin >> n >> q;
    for (int i = 0; i < n; i++)
        cin >> a[i];
}

void solve() {
    for (int i = 0; i < q; i++) {
        int op;
        cin >> op;
        if (op == 1) {
            int j, v;
            cin >> j >> v;
            j--;
            dp[j & 1][j / SQ] ^= a[j] ^ v;
            a[j] = v;
        }
        else {
            int l, r;
            cin >> l >> r;
            cout << ans(l - 1, r) << '\n';
        }
    }
}

int main() {
    ios:: sync_with_stdio(0), cin.tie(0), cout.tie(0);
    input();
    solve();
    return 0;
}

컴파일 시 표준 에러 (stderr) 메시지

xoranges.cpp: In function 'int ans(int, int)':
xoranges.cpp:8:21: warning: suggest parentheses around comparison in operand of '&' [-Wparentheses]
    8 |     if ((r - l) & 1 == 0)
      |                   ~~^~~~

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