Submission #819790

#	Time	Username	Problem	Language	Result	Execution time	Memory
819790		Andrijanikolic73	XORanges (eJOI19_xoranges)	C++17	0 / 100	1068 ms	7468 KiB

xoranges

#include <bits/stdc++.h>
#define pb push_back
#define ll long long
#define int long long
using namespace std;
const int N=2e5+50;
const int inf=1e18;
const int mod=1e9+7;
int a[N];
int n;
int q;
struct segtree{
    int t[4*N]={0};
    void build(int v,int tl,int tr){
        if(tl==tr)t[v]=a[tl];
        else {
            int tm=(tl+tr)/2;
            build(v*2,tl,tm);
            build(v*2+1,tm+1,tr);
            t[v]=(t[v*2]^t[v*2+1]);
        }
    }
    int query(int v,int tl,int tr,int l,int r){
        if(tr<l||tl>r)return 0;
        if(l<=tl&&tr<=r)return t[v];
        int tm=(tl+tr)/2;
        return (query(v*2,tl,tm,l,r)^query(v*2+1,tm+1,tr,l,r));
    }
    void update(int v,int tl,int tr,int index,int value){
        if(tl==tr){
            t[v]=value;
        }
        else {
            int tm=(tl+tr)/2;
            if(index<=tm){
                update(v*2,tl,tm,index,value);
            }
            else {
                update(v*2+1,tm+1,tr,index,value);
            }
            t[v]=(t[v*2]^t[v*2+1]);
        }
    }
};
segtree seg;
signed main(){
    ios::sync_with_stdio(false);
    cin.tie(0);
    cin>>n>>q;
    for(int i=1;i<=n;i++)cin>>a[i];
    seg.build(1,1,n);
    int pref[n+1];
    for(int i=0;i<=n;i++)pref[i]=0;
    while(q--){
        int o;
        cin>>o;
        if(o==1){
            int i,x;
            cin>>i>>x;
            a[i]=x;
        }
        else {
            int l,r;
            cin>>l>>r;
            if((r-l+1)%2==0){
                cout<<0;
                cout<<endl;
                continue;
            }
            int ans=0;
            for(int i=l;i<=r;i++){
                for(int j=i;j<=r;j++){
                    if(j%2)ans^=a[j];
                }
            }
            if(r-l+1==1)ans=a[r];
            cout<<ans;
            cout<<endl;
        }
    }
}

Compilation message (stderr)

xoranges.cpp: In function 'int main()':
xoranges.cpp:52:9: warning: variable 'pref' set but not used [-Wunused-but-set-variable]
   52 |     int pref[n+1];
      |         ^~~~

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