Submission #467885

#	Time	Username	Problem	Language	Result	Execution time	Memory
467885		alontanay	XORanges (eJOI19_xoranges)	C++14	100 / 100	670 ms	25140 KiB

xoranges

#include <bits/stdc++.h>

using namespace std;

struct Seg {
    int val = 0;
    int l,r,mid;
    Seg *ls, *rs;
    Seg(int l, int r): l(l), r(r), mid((l+r)/2) {
        if(l + 1 < r) {
            ls = new Seg(l, mid);
            rs = new Seg(mid, r);
        }
    }
    int query(int a, int b) {
        if(a >= r || b <= l) { return 0; }
        if(a <= l && b >= r) { return val; }
        return (ls->query(a,b))^(rs->query(a,b));
    }
    void update(int i, int x) {
        if(l + 1 == r) {
            val = x;
            return;
        }
        if(i < mid) { ls->update(i,x); } else { rs->update(i,x); }
        val = (ls->val)^(rs->val);
    }
};

int main() {
    ios::sync_with_stdio(false);
    cin.tie(0);

    int n,q,x,y,t;
    cin >> n >> q;
    Seg odd(0, (int)((n+1)/2));
    Seg even(0, n/2);
    for(int i = 0; i < n / 2; i ++) {
        cin >> x;
        odd.update(i, x);
        cin >> x;
        even.update(i, x);
    }
    if(n%2) {
        cin >> x;
        odd.update((n-1)/2, x);
    }
    for(int i = 0; i < q; i ++) {
        cin >> t >> x >> y; x--;
        if(t == 1) {
            if(x%2) {
                even.update(x/2, y);
            } else {
                odd.update(x/2, y);
            }
        } else {
            if((y - x)%2) {
                if(x%2) {
                    cout << even.query(x/2,(y+1)/2) << endl;
                } else {
                    cout << odd.query(x/2,(y+1)/2) << endl;
                }
            } else {
                cout << 0 << endl;
            }
        }
    }
    return 0;
}

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