Submission #1335052

#	Time	Username	Problem	Language	Result	Execution time	Memory
1335052		lunarecho	Mountains (NOI20_mountains)	C++20	2 / 100	300 ms	23920 KiB

Mountains

#include <bits/stdc++.h>
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>
using namespace std;
#define ll long long
typedef __gnu_pbds::tree<ll, __gnu_pbds::null_type, less<ll>, 
        __gnu_pbds::rb_tree_tag, __gnu_pbds::tree_order_statistics_node_update> ordered_set;
#define ll long long
#define F first
#define S second


int main() {
    ios::sync_with_stdio(false);
    cin.tie(nullptr);

    int n;
    cin>>n;
    vector<ll> a(n), b(n);
    ordered_set os;
    for(int i=0;i<n;++i) {
        cin>>a[i];
        b[i] = os.order_of_key(a[i]);
        os.insert(a[i]);
    }
    os.clear();
    ll ans = 0;
    for(int i=n-1;i>=0;--i) {
        ans += (b[i] * os.order_of_key(a[i]));
        os.insert(a[i]);
    }
    cout<<ans<<'\n';

    return 0;
}

• Subtask 1: 2 / 2
• Subtask 2: 0 / 4
• Subtask 3: 0 / 9
• Subtask 4: 0 / 36
• Subtask 5: 0 / 28
• Subtask 6: 0 / 9
• Subtask 7: 0 / 12