Submission #1246278

#	Time	Username	Problem	Language	Result	Execution time	Memory
1246278		nanaseyuzuki	XORanges (eJOI19_xoranges)	C++20	100 / 100	53 ms	3912 KiB

xoranges

#include <bits/stdc++.h>
/*
    --> Author: Kazuki_Hoshino__8703 <--
    I love Nanasaki Ai ☆*: .｡. o(≧▽≦)o .｡.:*☆
*/
#define fi first
#define se second
#define pii pair<int, int>
#define ll long long
using namespace std;

const int mn = 3e5 + 5, bm = (1 << 15) + 1, mod = 1e9 + 7;
const ll inf = 1e9 + 7, base = 311;

int n, q, a[mn];

int bit[2][mn];

void add(int x, int u, int val){
    while(u <= n){
        bit[x][u] ^= val;
        u += (u & -u);
    }
}

int get(int x, int u){
    int res = 0;
    while(u > 0){
        res ^= bit[x][u];
        u -= (u & -u);
    }
    return res;
}

void solve(){
    cin >> n >> q;
    for(int i = 1; i <= n; i++){
        cin >> a[i];
        add(i % 2, i, a[i]);
    }
    while(q--){
        int t, l, r; cin >> t >> l >> r;
        if(t == 1){
            add(l % 2, l, a[l]);
            add(l % 2, l, r);
            a[l] = r;
        }
        else{
            int len = r - l + 1;
            if(len % 2 == 0) cout << 0 << '\n';
            else{
                int id = l % 2;
                cout << (get(id, r) ^ get(id, l - 1)) << '\n';
            }
        }
    }
}

signed main(){
    ios_base::sync_with_stdio(false);
    cin.tie(NULL);
    if(fopen("ROBOT.INP", "r")){
        freopen("ROBOT.INP", "r", stdin);
        freopen("ROBOT.OUT", "w", stdout);
    }
    int t = 1;
    // cin >> t;
    while(t --){
        solve();
    }
}

Compilation message (stderr)

xoranges.cpp: In function 'int main()':
xoranges.cpp:63:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   63 |         freopen("ROBOT.INP", "r", stdin);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~
xoranges.cpp:64:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   64 |         freopen("ROBOT.OUT", "w", stdout);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~

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