oj.uz

Submission #763693

# Submission time Handle Problem Language Result Execution time Memory
763693 2023-06-22T16:00:17 Z GrindMachine Žarulje (COI15_zarulje) C++17
100 / 100
 179 ms 25252 KB 
// Om Namah Shivaya

#include <bits/stdc++.h>
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>

using namespace std;
using namespace __gnu_pbds;

template<typename T> using Tree = tree<T, null_type, less<T>, rb_tree_tag, tree_order_statistics_node_update>;
typedef long long int ll;
typedef long double ld;
typedef pair<int, int> pii;
typedef pair<ll, ll> pll;

#define fastio ios_base::sync_with_stdio(false); cin.tie(NULL)
#define pb push_back
#define endl '\n'
#define sz(a) a.size()
#define setbits(x) __builtin_popcountll(x)
#define ff first
#define ss second
#define conts continue
#define ceil2(x, y) ((x + y - 1) / (y))
#define all(a) a.begin(), a.end()
#define rall(a) a.rbegin(), a.rend()
#define yes cout << "Yes" << endl
#define no cout << "No" << endl

#define rep(i, n) for(int i = 0; i < n; ++i)
#define rep1(i, n) for(int i = 1; i <= n; ++i)
#define rev(i, s, e) for(int i = s; i >= e; --i)
#define trav(i, a) for(auto &i : a)

template<typename T>
void amin(T &a, T b) {
    a = min(a, b);
}

template<typename T>
void amax(T &a, T b) {
    a = max(a, b);
}

#ifdef LOCAL
#include "debug.h"
#else
#define debug(x) 42
#endif

/*

refs:
edi
https://github.com/farmerboy95/CompetitiveProgramming/blob/92f327caaade93b9087bc969d8ed6fa4f596048c/COI/COI%2015-zarulje.cpp

*/

const int MOD = 1e9 + 7;
const int N = 2e5 + 5;
const int inf1 = int(1e9) + 5;
const ll inf2 = ll(1e18) + 5;

ll fact[N], ifact[N];

ll bexp(ll a, ll b) {
    a %= MOD;
    if (a == 0) return 0;

    ll res = 1;

    while (b) {
        if (b & 1) res = res * a % MOD;
        a = a * a % MOD;
        b >>= 1;
    }

    return res;
}

ll invmod(ll a) {
    return bexp(a, MOD - 2);
}

ll ncr(ll n, ll r) {
    if (n < 0 or r < 0 or n < r) return 0;
    return fact[n] * ifact[r] % MOD * ifact[n - r] % MOD;
}

ll npr(ll n, ll r) {
    if (n < 0 or r < 0 or n < r) return 0;
    return fact[n] * ifact[n - r] % MOD;
}

void precalc(ll n) {
    fact[0] = 1;
    rep1(i, n) fact[i] = fact[i - 1] * i % MOD;

    ifact[n] = invmod(fact[n]);
    rev(i, n - 1, 0) ifact[i] = ifact[i + 1] * (i + 1) % MOD;
}

void solve(int test_case)
{
    ll n,k; cin >> n >> k;
    precalc(n);

    vector<ll> a(n+5), b(k+5);
    rep1(i,n) cin >> a[i];
    rep1(i,k) cin >> b[i];

    vector<ll> ans(n+5);
    vector<pll> cnt(N);
    ll res = 1;

    auto upd = [&](ll i, ll j, ll c){
        auto &[x,y] = cnt[i];
        res = res * invmod(ncr(x+y,x)) % MOD;
        if(j == 1) x += c;
        else y += c;
        res = res * ncr(x+y,x) % MOD;
    };

    vector<ll> lx(n+5,1);
    stack<ll> st;

    rev(i,n,1){
        while(!st.empty() and a[i] < a[st.top()]){
            lx[st.top()] = i;
            st.pop();
        }
        st.push(i);
    }

    while(!st.empty()) st.pop();

    vector<ll> enter[n+5];
    rep1(i,n){
        enter[lx[i]].pb(i);
    }

    rep1(i,n){
        trav(j,enter[i]){
            upd(a[j],2,1);
        }
        upd(a[i],2,-1);

        ans[i] = res;

        while(!st.empty() and a[i] < a[st.top()]){
            upd(a[st.top()],1,-1);
            st.pop();
        }

        st.push(i);
        upd(a[i],1,1);
    }

    rep1(i,k){
        cout << ans[b[i]] << endl;
    }

    // rep1(ind,k){
    //     ll p = b[ind];
    //     ll mn = inf2;
    //     map<ll,pll> mp;

    //     for(int i = p+1; i <= n; ++i){
    //         if(a[i] > mn){
    //             // will def be removed without any option
    //             conts;
    //         }

    //         mn = a[i];
    //         mp[a[i]].ff++;
    //     }

    //     mn = inf2;
    //     rev(i,p-1,1){
    //         if(a[i] > mn){
    //             // will def be removed without any option
    //             conts;
    //         }

    //         mn = a[i];
    //         mp[a[i]].ss++;
    //     }

    //     ll ans = 1;
    //     for(auto [val,px] : mp){
    //         ll ways = ncr(px.ff+px.ss, px.ff);
    //         ans = ans * ways % MOD;
    //     }

    //     cout << ans << endl;
    // }
}

int main()
{
    fastio;

    int t = 1;
    // cin >> t;

    rep1(i, t) {
        solve(i);
    }

    return 0;
}

Subtask #1
22.0 / 22.0

# Verdict Execution time Memory Grader output
1 Correct 2 ms 3412 KB Output is correct
2 Correct 2 ms 3540 KB Output is correct
3 Correct 4 ms 3668 KB Output is correct
4 Correct 3 ms 3540 KB Output is correct
5 Correct 3 ms 3540 KB Output is correct
6 Correct 3 ms 3652 KB Output is correct

Subtask #2
38.0 / 38.0

# Verdict Execution time Memory Grader output
1 Correct 69 ms 11528 KB Output is correct
2 Correct 135 ms 19544 KB Output is correct
3 Correct 136 ms 19712 KB Output is correct
4 Correct 136 ms 19624 KB Output is correct
5 Correct 143 ms 19668 KB Output is correct
6 Correct 149 ms 19816 KB Output is correct
7 Correct 144 ms 19704 KB Output is correct

Subtask #3
40.0 / 40.0

# Verdict Execution time Memory Grader output
1 Correct 2 ms 3412 KB Output is correct
2 Correct 2 ms 3540 KB Output is correct
3 Correct 4 ms 3668 KB Output is correct
4 Correct 3 ms 3540 KB Output is correct
5 Correct 3 ms 3540 KB Output is correct
6 Correct 3 ms 3652 KB Output is correct
7 Correct 69 ms 11528 KB Output is correct
8 Correct 135 ms 19544 KB Output is correct
9 Correct 136 ms 19712 KB Output is correct
10 Correct 136 ms 19624 KB Output is correct
11 Correct 143 ms 19668 KB Output is correct
12 Correct 149 ms 19816 KB Output is correct
13 Correct 144 ms 19704 KB Output is correct
14 Correct 9 ms 4436 KB Output is correct
15 Correct 82 ms 13276 KB Output is correct
16 Correct 159 ms 24856 KB Output is correct
17 Correct 161 ms 22604 KB Output is correct
18 Correct 161 ms 25252 KB Output is correct
19 Correct 152 ms 22472 KB Output is correct
20 Correct 179 ms 23976 KB Output is correct
21 Correct 168 ms 24104 KB Output is correct