Submission #456247

#	Time	Username	Problem	Language	Result	Execution time	Memory
456247		SamAnd	XORanges (eJOI19_xoranges)	C++17	100 / 100	214 ms	13072 KiB

xoranges

#include <bits/stdc++.h>
using namespace std;
#define m_p make_pair
#define all(x) (x).begin(),(x).end()
#define sz(x) ((int)(x).size())
#define fi first
#define se second
typedef long long ll;
mt19937 rnd(chrono::steady_clock::now().time_since_epoch().count());
mt19937 rnf(2106);
const int N = 200005;

int n, qq;
int a[N];

void ubd(vector<int>& t, int tl, int tr, int x, int y, int pos)
{
    if (tl == tr)
    {
        t[pos] = y;
        return;
    }
    int m = (tl + tr) / 2;
    if (x <= m)
        ubd(t, tl, m, x, y, pos * 2);
    else
        ubd(t, m + 1, tr, x, y, pos * 2 + 1);
    t[pos] = (t[pos * 2] ^ t[pos * 2 + 1]);
}

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

void solv()
{
    cin >> n >> qq;
    for (int i = 1; i <= n; ++i)
        cin >> a[i];

    vector<int> t[2];
    t[0].assign(n * 4 + 10, 0);
    t[1].assign(n * 4 + 10, 0);

    for (int i = 1; i <= n; ++i)
        ubd(t[(i % 2)], 1, n, i, a[i], 1);

    while (qq--)
    {
        int ty;
        cin >> ty;
        if (ty == 1)
        {
            int x, y;
            cin >> x >> y;
            ubd(t[(x % 2)], 1, n, x, y, 1);
        }
        else
        {
            int l, r;
            cin >> l >> r;
            if ((r - l + 1) % 2 == 0)
                cout << "0\n";
            else
                cout << qry(t[(l % 2)], 1, n, l, r, 1) << "\n";
        }
    }
}

int main()
{
    #ifdef SOMETHING
    freopen("input.txt", "r", stdin);
    //freopen("output.txt", "w", stdout);
    #endif // SOMETHING
    ios_base::sync_with_stdio(false), cin.tie(0);

    int tt = 1;
    //cin >> tt;
    while (tt--)
    {
        solv();
    }
    return 0;
}

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