Submission #968055

#	Time	Username	Problem	Language	Result	Execution time	Memory
968055		vjudge1	Vudu (COCI15_vudu)	C++17	126 / 140	709 ms	58580 KiB

vudu

#include<bits/stdc++.h>
 
using namespace std;
 
int n;
unordered_map<int, int> fw;
long long ans;
 
void update(int idx, int val){
    for(; idx <= n; idx+=(idx&-idx)) fw[idx]+=val;
}
 
long long query(int idx){
    long long sum = 0;
    for(; idx; idx-=(idx&-idx)) sum+=fw[idx];
    return sum;
}
 
signed main(){
    cin.tie(nullptr)->sync_with_stdio(false);
    cin >> n;
    long long qs[n+1], k;
    vector<long long> v;
    memset(qs, 0, sizeof(qs));
    for(int i = 1; i<=n; ++i) cin >> qs[i];
    cin >> k;
    for(int i = 1; i<=n; ++i) qs[i]+=qs[i - 1];
    for(int i = 1; i<=n; ++i) v.push_back(qs[i] - i*k);
    sort(v.begin(), v.end());
    v.erase(unique(v.begin(), v.end()));
    for(int i = 0; i<=n; ++i){
        int id = lower_bound(v.begin(), v.end(), qs[i] - i*k) - v.begin();
        ans+=query(id+1);
        update(id+1, 1);
    }
    cout << ans;
}

• Subtask 1: 126 / 140