oj.uz

Submission #756068

# Submission time Handle Problem Language Result Execution time Memory
756068 2023-06-11T03:26:16 Z browntoad Kangaroo (CEOI16_kangaroo) C++14
100 / 100
 21 ms 22996 KB 
#include <bits/stdc++.h>
#pragma GCC optimize ("Ofast", "unroll-loops")
using namespace std;
#define ll long long
#define int ll
#define FOR(i,a,b) for (int i = (a); i<(b); i++)
#define REP(i,n) FOR(i,0,n)
#define REP1(i,n) FOR(i,1,n+1)
#define RREP(i,n) for (int i=(n)-1; i>=0; i--)
#define f first
#define s second
#define pb push_back
#define ALL(x) x.begin(),x.end()
#define SZ(x) (int)(x.size())
#define SQ(x) (x)*(x)
#define pii pair<int, int>
#define pip pair<int, pii>
#define pdd pair<double ,double>
#define pcc pair<char, char>
#define endl '\n'
//#define TOAD
#ifdef TOAD
#define bug(x) cerr<<__LINE__<<": "<<#x<<" is "<<x<<endl
#define IOS()
#else
#define bug(...)
#define IOS() ios::sync_with_stdio(0), cin.tie(0), cout.tie(0)
#endif

const ll inf = 1ll<<60;
const ll iinf = 2147483647;
const ll mod = 1e9+7;
const ll maxn = 2005;
const ll maxm = 2005;
const double PI=acos(-1);

ll pw(ll x, ll p, ll m=mod){
    ll ret=1;
    while (p>0){
        if (p&1){
            ret*=x;
            ret%=m;
        }
        x*=x;
        x%=m;
        p>>=1;
    }
    return ret;
}

ll inv(ll a, ll m=mod){
    return pw(a,m-2,m);
}
int dp[maxn][maxn];
signed main(){
    IOS();
    int n, cs, cf; cin>>n>>cs>>cf;
    if (cs > cf) swap(cs, cf);
    dp[0][0] = 1;
    REP1(i, n){
        REP1(j, i){
            if (i < cs){
                dp[i][j] = dp[i-1][j-1] + dp[i-1][j+1]*(j+1)%mod*j%mod;
            }
            if (i == cs){
                dp[i][j] = dp[i-1][j-1] + dp[i-1][j]*j%mod;
            }
            if (i > cs && i < cf){
                dp[i][j] = dp[i-1][j-1] + dp[i-1][j+1]*j%mod*j%mod; // j * (j-1) + 1 * j
            }
            if (i == cf){
                if (i == n && j == 1) dp[i][j] = dp[i-1][j];
                else dp[i][j] = dp[i-1][j-1] + dp[i-1][j]*(j-1)%mod;
            }
            if (i > cf){
                if (i == n && j == 1) dp[i][j] = dp[i-1][j+1];
                else dp[i][j] = dp[i-1][j-1] + dp[i-1][j+1]*(j-1)%mod*j%mod;
            }
            dp[i][j] %= mod;
        }
    }
    cout<<dp[n][1]<<endl;
}

Subtask #1
6.0 / 6.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 340 KB Output is correct
2 Correct 1 ms 324 KB Output is correct

Subtask #2
30.0 / 30.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 340 KB Output is correct
2 Correct 1 ms 324 KB Output is correct
3 Correct 1 ms 336 KB Output is correct
4 Correct 1 ms 460 KB Output is correct
5 Correct 1 ms 460 KB Output is correct
6 Correct 0 ms 468 KB Output is correct
7 Correct 0 ms 468 KB Output is correct
8 Correct 0 ms 460 KB Output is correct
9 Correct 0 ms 468 KB Output is correct
10 Correct 1 ms 468 KB Output is correct
11 Correct 0 ms 468 KB Output is correct

Subtask #3
15.0 / 15.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 340 KB Output is correct
2 Correct 1 ms 324 KB Output is correct
3 Correct 1 ms 336 KB Output is correct
4 Correct 1 ms 460 KB Output is correct
5 Correct 1 ms 460 KB Output is correct
6 Correct 0 ms 468 KB Output is correct
7 Correct 0 ms 468 KB Output is correct
8 Correct 0 ms 460 KB Output is correct
9 Correct 0 ms 468 KB Output is correct
10 Correct 1 ms 468 KB Output is correct
11 Correct 0 ms 468 KB Output is correct
12 Correct 1 ms 1224 KB Output is correct
13 Correct 1 ms 1108 KB Output is correct
14 Correct 1 ms 1240 KB Output is correct
15 Correct 1 ms 1228 KB Output is correct
16 Correct 2 ms 1236 KB Output is correct
17 Correct 1 ms 1236 KB Output is correct
18 Correct 1 ms 1100 KB Output is correct
19 Correct 1 ms 1236 KB Output is correct
20 Correct 1 ms 1236 KB Output is correct

Subtask #4
49.0 / 49.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 340 KB Output is correct
2 Correct 1 ms 324 KB Output is correct
3 Correct 1 ms 336 KB Output is correct
4 Correct 1 ms 460 KB Output is correct
5 Correct 1 ms 460 KB Output is correct
6 Correct 0 ms 468 KB Output is correct
7 Correct 0 ms 468 KB Output is correct
8 Correct 0 ms 460 KB Output is correct
9 Correct 0 ms 468 KB Output is correct
10 Correct 1 ms 468 KB Output is correct
11 Correct 0 ms 468 KB Output is correct
12 Correct 1 ms 1224 KB Output is correct
13 Correct 1 ms 1108 KB Output is correct
14 Correct 1 ms 1240 KB Output is correct
15 Correct 1 ms 1228 KB Output is correct
16 Correct 2 ms 1236 KB Output is correct
17 Correct 1 ms 1236 KB Output is correct
18 Correct 1 ms 1100 KB Output is correct
19 Correct 1 ms 1236 KB Output is correct
20 Correct 1 ms 1236 KB Output is correct
21 Correct 4 ms 4564 KB Output is correct
22 Correct 4 ms 5068 KB Output is correct
23 Correct 4 ms 5588 KB Output is correct
24 Correct 20 ms 22996 KB Output is correct
25 Correct 20 ms 22908 KB Output is correct
26 Correct 21 ms 22980 KB Output is correct
27 Correct 21 ms 22856 KB Output is correct
28 Correct 13 ms 15052 KB Output is correct