Submission #1071797

#	Time	Username	Problem	Language	Result	Execution time	Memory
1071797		ezzzay	Index (COCI21_index)	C++14	60 / 110	2548 ms	76904 KiB

index

#include<bits/stdc++.h>
using namespace std;
#define int long long
#define ff first
#define ss second
#define pb push_back
const int N=3e5+5;
int L[N],R[N];
int a[N];
vector<int>ans;
vector<int>st[N*4];
void merge(int x){
    st[x].clear();
    for(auto p:st[x*2])st[x].pb(p);
    for(auto p:st[x*2+1])st[x].pb(p);
    sort(st[x].begin(),st[x].end());
}
void build(int node, int L, int R){
    if(L==R){
        st[node].pb(a[L]);
        return;
    }
    int mid=(L+R)/2;
    build(node*2,L,mid);
    build(node*2+1,mid+1,R);
    merge(node);
}
int check(int val, int x){
    val--;
    auto it=upper_bound(st[x].begin(),st[x].end(),val);
    int p=0;
    return st[x].size()-(it-st[x].begin());
}
int find(int node, int L, int R, int l, int r, int val){
    if(r<L or R<l)return 0;
    if(l<=L and R<=r){
        return check(val,node);
    }
    int mid=(L+R)/2;
    return(find(node*2,L,mid,l,r,val)+find(node*2+1,mid+1,R,l,r,val));
}
signed main(){
    int n,q;
    cin>>n>>q;
    
    for(int i=1;i<=n;i++){
        cin>>a[i];
    }
    build(1,1,n);
    while(q--){
        int l,r;
        cin>>l>>r;
        int lo=0,hi=1e9;
        while(hi>=lo){
            int mid=(hi+lo)/2;
            int k=find(1,1,n,l,r,mid);
            if(k>=mid){
                lo=mid+1;
            }
            else{
                hi=mid-1;
            }
        }
        ans.pb(hi);
    }
    for(auto p:ans)cout<<p<<endl;
}

Compilation message (stderr)

index.cpp: In function 'long long int check(long long int, long long int)':
index.cpp:31:9: warning: unused variable 'p' [-Wunused-variable]
   31 |     int p=0;
      |         ^

• Subtask 1: 20 / 20
• Subtask 2: 40 / 40
• Subtask 3: 0 / 50