oj.uz

Submission #604956

# Submission time Handle Problem Language Result Execution time Memory
604956 2022-07-25T11:09:33 Z generic_placeholder_name Kangaroo (CEOI16_kangaroo) C++17
100 / 100
 15 ms 384 KB 
#pragma GCC optimize("Ofast")
#pragma GCC optimize("unroll-loops")
#pragma GCC target("avx,avx2,fma,popcnt")

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

using namespace std;
using namespace __gnu_pbds;
using namespace __gnu_cxx;

mt19937_64 rng(chrono::steady_clock::now().time_since_epoch().count());

#define fi first
#define se second
#define pb push_back
#define eb emplace_back
#define mp make_pair
#define gcd __gcd
#define fastio ios_base::sync_with_stdio(0); cin.tie(0); cout.tie(0)
#define rep(i, n) for (int i=0; i<(n); i++)
#define rep1(i, n) for (int i=1; i<=(n); i++)
#define all(x) (x).begin(), (x).end()
#define rall(x) (x).rbegin(), (x).rend()
#define endl "\n"

typedef long long ll;
typedef unsigned long long ull;
typedef unsigned uint;
typedef long double ld;
typedef pair<int, int> pii;
typedef pair<ll, ll> pll;
typedef vector<int> vi;
typedef vector<vector<int>> vvi;
typedef vector<ll> vll;
typedef vector<vector<ll>> vvll;
typedef vector<bool> vb;
typedef vector<vector<bool>> vvb;
template<typename T, typename cmp = less<T>>
using ordered_set = tree<T, null_type, cmp, rb_tree_tag, tree_order_statistics_node_update>;
typedef trie<string, null_type, trie_string_access_traits<>, pat_trie_tag, trie_prefix_search_node_update> pref_trie;

constexpr int N = 2005;
constexpr int MOD = 1e9 + 7;
int dp[2][N];

void sadd(int& a, int b) {if((a += b) >= MOD) a -= MOD;}
int mul(int a, int b) {return (a * 1LL * b) % MOD;}

int32_t main() {
    fastio;
    int n, s, f; cin >> n >> s >> f; --s, --f;
    int *prv = dp[0], *nxt = dp[1];
    size_t fuck = sizeof(dp[0]);
    prv[1] = 1;
    rep1(i, n - 1) {
        memset(nxt, 0, fuck);
        for(int j = 1; j <= i; j++) {
            if(i == s || i == f) {
                sadd(nxt[j], prv[j]);
                sadd(nxt[j + 1], prv[j]);
            }
            else {
                sadd(nxt[j + 1], mul(prv[j], j + 1 - (i > s) - (i > f)));
                sadd(nxt[j - 1], mul(prv[j], j - 1));
            }
        }
        swap(prv, nxt);
    }
    cout << prv[1] << endl;
}

Subtask #1
6.0 / 6.0

# Verdict Execution time Memory Grader output
1 Correct 0 ms 212 KB Output is correct
2 Correct 0 ms 212 KB Output is correct

Subtask #2
30.0 / 30.0

# Verdict Execution time Memory Grader output
1 Correct 0 ms 212 KB Output is correct
2 Correct 0 ms 212 KB Output is correct
3 Correct 0 ms 212 KB Output is correct
4 Correct 0 ms 340 KB Output is correct
5 Correct 0 ms 212 KB Output is correct
6 Correct 0 ms 212 KB Output is correct
7 Correct 0 ms 212 KB Output is correct
8 Correct 0 ms 212 KB Output is correct
9 Correct 0 ms 212 KB Output is correct
10 Correct 0 ms 212 KB Output is correct
11 Correct 0 ms 212 KB Output is correct

Subtask #3
15.0 / 15.0

# Verdict Execution time Memory Grader output
1 Correct 0 ms 212 KB Output is correct
2 Correct 0 ms 212 KB Output is correct
3 Correct 0 ms 212 KB Output is correct
4 Correct 0 ms 340 KB Output is correct
5 Correct 0 ms 212 KB Output is correct
6 Correct 0 ms 212 KB Output is correct
7 Correct 0 ms 212 KB Output is correct
8 Correct 0 ms 212 KB Output is correct
9 Correct 0 ms 212 KB Output is correct
10 Correct 0 ms 212 KB Output is correct
11 Correct 0 ms 212 KB Output is correct
12 Correct 1 ms 212 KB Output is correct
13 Correct 0 ms 340 KB Output is correct
14 Correct 1 ms 212 KB Output is correct
15 Correct 1 ms 340 KB Output is correct
16 Correct 0 ms 212 KB Output is correct
17 Correct 0 ms 212 KB Output is correct
18 Correct 0 ms 212 KB Output is correct
19 Correct 1 ms 212 KB Output is correct
20 Correct 0 ms 212 KB Output is correct

Subtask #4
49.0 / 49.0

# Verdict Execution time Memory Grader output
1 Correct 0 ms 212 KB Output is correct
2 Correct 0 ms 212 KB Output is correct
3 Correct 0 ms 212 KB Output is correct
4 Correct 0 ms 340 KB Output is correct
5 Correct 0 ms 212 KB Output is correct
6 Correct 0 ms 212 KB Output is correct
7 Correct 0 ms 212 KB Output is correct
8 Correct 0 ms 212 KB Output is correct
9 Correct 0 ms 212 KB Output is correct
10 Correct 0 ms 212 KB Output is correct
11 Correct 0 ms 212 KB Output is correct
12 Correct 1 ms 212 KB Output is correct
13 Correct 0 ms 340 KB Output is correct
14 Correct 1 ms 212 KB Output is correct
15 Correct 1 ms 340 KB Output is correct
16 Correct 0 ms 212 KB Output is correct
17 Correct 0 ms 212 KB Output is correct
18 Correct 0 ms 212 KB Output is correct
19 Correct 1 ms 212 KB Output is correct
20 Correct 0 ms 212 KB Output is correct
21 Correct 2 ms 212 KB Output is correct
22 Correct 2 ms 384 KB Output is correct
23 Correct 3 ms 212 KB Output is correct
24 Correct 14 ms 332 KB Output is correct
25 Correct 13 ms 332 KB Output is correct
26 Correct 15 ms 332 KB Output is correct
27 Correct 14 ms 308 KB Output is correct
28 Correct 8 ms 212 KB Output is correct