Submission #638713

#	Time	Username	Problem	Language	Result	Execution time	Memory
638713		SalihSahin	XORanges (eJOI19_xoranges)	C++14	38 / 100	85 ms	10872 KiB

xoranges

#include <bits/stdc++.h>
#define pb push_back
#define fastio cin.tie(0); ios_base::sync_with_stdio(false); cout.tie(0)
#define endl "\n"
#define all(v) v.begin(),v.end()
#define int long long
using namespace std;

const int INF = 1e17, MOD = 1e9 + 7, N = 6e5 + 5, MOD2 = 998244353;

int fpow(int a, int b){  // returns a to the power of b %MOD
 if(b == 0) return 1;
 if(b == 1) return a;
 int x = fpow(a,b/2)%MOD;
 if(b%2) return ((x*x)%MOD*a)%MOD;
 else return (x*x)%MOD;
}


int32_t main(){
  fastio;
  int n, q;
  cin>>n>>q;

  vector<int> a(n + 1), oddxr(n + 1), evenxr(n + 1);
  for(int i = 1; i <= n; i++){
    cin>>a[i];
    if(i == 1) oddxr[i] = a[i];
    else if(i == 2) evenxr[i] = a[i];
    else if(i&1) oddxr[i] = a[i]^oddxr[i-2];
    else evenxr[i] = a[i]^evenxr[i-2];
  }

  while(q--){
    int type;
    cin>>type;

    if(type == 1){
        int ind, x;
        cin>>ind>>x;
        a[ind] = x;
    }
    else{ // type == 2
        int l, u;
        cin>>l>>u;
        if((u - l + 1)&1){
          int res;
          if(l == 1) res = oddxr[u];
          else if(l == 2) res = evenxr[u];
          else if(l&1) res = oddxr[u]^oddxr[l-2];
          else res = evenxr[u]^evenxr[l-2];

          cout<<res<<endl;
        }
        else{
            cout<<0<<endl;
        }
    }
  }
  return 0;
}

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