Submission #1230656

#	Time	Username	Problem	Language	Result	Execution time	Memory
1230656		hitsuuj	Vudu (COCI15_vudu)	C++20	42 / 140	1099 ms	131072 KiB

vudu

#include <bits/stdc++.h>
using namespace std;
#define int long long
#define pb push_back
#define pii pair<int,int>
#define fi first
#define se second
#define inf LLONG_MAX
#define ti tuple<int,int,int>
const int lim=1e6; 
vector<int>tri(lim+10);
map<int,int>cm;
int n,m;
int seek(int x){
    int cnt=0;
    while(x>=1){
        cnt+=tri[x];
        x-=x&-x;
    }
    return cnt;
}
void upd(int x){
    while(x<=n){
        tri[x]++;
        x+=x&-x;
    }
}
signed main(){
    cin>>n;vector<int>a(n+1);for(int i=1;i<=n;i++) cin>>a[i];
    int p;cin>>p;
    int pref=0;
    int ans=0;
    set<int>c;
    for(int i=1;i<=n;i++){
        pref+=a[i];
        a[i]=pref-p*i;
        c.insert(a[i]);
    }
    c.insert(0);
    vector<int>sorted;
    for(auto x:c) sorted.pb(x);
    for(int i=0;i<sorted.size();i++){
        cm[sorted[i]]=i+1;
    }
    m=sorted.size();
    upd(cm[0]);
    for(int i=1;i<=n;i++){
        // cout<<"cek "<<cm[a[i]]<<" "<<seek(cm[a[i]])<<endl;
        ans+=seek(cm[a[i]]);
        upd(cm[a[i]]);
        // cout<<i<<" "<<seek(cm[a[i]])<<endl;
    }
    cout<<ans;

}

// (pref[r]-pref[l-1])>= p(r-l+1)
// pref[r]-pr>=pref[l-1]-pl+p

• Subtask 1: 42 / 140