Submission #312828

#	Time	Username	Problem	Language	Result	Execution time	Memory
312828		daringtrifles	Mountains (NOI20_mountains)	C++17	36 / 100	2097 ms	13304 KiB

Mountains

//control+option+n to run!
#include <bits/stdc++.h>
using namespace std;
#define pb push_back
#define ll long long
#define pll pair<ll, ll>
#define FOR(i, a, b) for (signed long long i = (signed long long)(a); i < (signed long long)(b); i++)
#define NEGFOR(i, a, b) for (ll i = (a); i > (b); i--)
#define vll vector<long long>
#define sll set<long long>
#define ld long double
#define inf 1000000000000000000
#define mll multiset<long long>
#define vpll vector<pll>
#define nn << "\n"
#define ss << " "
#define F(i, b) for (ll i = 0; i < b; i++)
//10^8 operations per second
//greatest int is 2,147,483,647
//greates long long is 9.22337204e18

//ALL FUNCTIONS SHOULD BE LL!!!!
ll power(ll x, ll n, ll m)
{
    assert(n >= 0);
    x %= m; //note: m*m must be less than 2^63 to avoid ll overflow
    ll res = 1;
    while (n > 0)
    {
        if (n % 2 == 1) //if n is odd
            res = res * x % m;
        x = x * x % m;
        n /= 2; //divide by two
    }
    return res;
}

ll log(ll base, ll number)
{

    int x = base;
    int count = 1;
    while (base < number)
    {
        base *= x;
        count++;
    }
    return count;
}
//#define oi
int main()
{
#ifdef oi
    ifstream cin("file.in");
    ofstream cout("file.out");
#endif
#ifndef oi
    ios_base::sync_with_stdio(false);
    cin.tie(NULL);
#endif
    clock_t tStart = clock();
    ll n;
    cin >> n;
    vll v(n);
    FOR(i, 0, n)
        cin >> v[i];
    vll before(n, 0), after(n, 0), x;
    ll ans = 0;


    x.pb(v[0]);
    FOR(i, 1, n)
    {
        before[i] = lower_bound(x.begin(), x.end(), v[i]) - x.begin();
        x.pb(v[i]);
        sort(x.begin(), x.end());
    }

    x={};

    reverse(v.begin(),v.end());
    x.pb(v[0]);
    FOR(i, 1, n)
    {
        after[i] = lower_bound(x.begin(), x.end(), v[i])-x.begin();
        x.pb(v[i]);
        sort(x.begin(), x.end());
    }
    //for (auto i:v) cout<< i ss;
    reverse(after.begin(),after.end());
    FOR(i,0,n){
        ans+=before[i]*after[i];
    }
    cout<<ans;
    cerr nn << (double)(clock() - tStart) / CLOCKS_PER_SEC;
}

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