oj.uz

Submission #481293

# Submission time Handle Problem Language Result Execution time Memory
481293 2021-10-20T09:47:43 Z Markadiusz Kangaroo (CEOI16_kangaroo) C++17
100 / 100
 37 ms 31732 KB 
#include <bits/stdc++.h>
using namespace std;
using LL=long long;
#define FOR(i,l,r) for(int i=(l);i<=(r);++i)
#define REP(i,n) FOR(i,0,(n)-1)
#define ssize(x) int(x.size())
template<class A,class B>auto&operator<<(ostream&o,pair<A,B>p){return o<<'('<<p.first<<", "<<p.second<<')';}
template<class T>auto operator<<(ostream&o,T x)->decltype(x.end(),o){o<<'{';int i=0;for(auto e:x)o<<(", ")+2*!i++<<e;return o<<'}';}
#ifdef DEBUG
#define debug(x...) cerr<<"["#x"]: ",[](auto...$){((cerr<<$<<"; "),...);}(x),cerr<<'\n'
#else
#define debug(...) {}
#endif

int main() {
	cin.tie(0)->sync_with_stdio(0);
	
	const long long mod = 1e9 + 7;
	int n, cs, cf;
	cin >> n >> cs >> cf;
	debug(n, cs, cf);
	if (cs > cf) {
		swap(cs, cf);
	}
	debug(cs, cf);
	vector <vector <long long> >dp(n + 1, vector <long long> (n + 1, 0ll));
	dp[1][1] = 1;
	FOR(i, 1, n - 1) {
		FOR(j, 1, n - 1) {
			if (i + 1 == cs || i + 1 == cf) {
				dp[i + 1][j + 1] = (dp[i + 1][j + 1] + dp[i][j]) % mod;
				dp[i + 1][j] = (dp[i + 1][j] + dp[i][j]) % mod;
			}
			else if (i < cs) {
				dp[i + 1][j + 1] = (dp[i + 1][j + 1] + dp[i][j] * (j + 1)) % mod;
				dp[i + 1][j - 1] = (dp[i + 1][j - 1] + dp[i][j] * (j - 1)) % mod;
			}
			else if (i < cf) {
				dp[i + 1][j + 1] = (dp[i + 1][j + 1] + dp[i][j] * j) % mod;
                                dp[i + 1][j - 1] = (dp[i + 1][j - 1] + dp[i][j] * (j - 1)) % mod;
			}
			else { // i >= cf
				dp[i + 1][j + 1] = (dp[i + 1][j + 1] + dp[i][j] * (j - 1)) % mod;
                                dp[i + 1][j - 1] = (dp[i + 1][j - 1] + dp[i][j] * (j - 1)) % mod;
			}
		}
	}
	debug(dp);
	cout << dp[n][1] << endl;
	
}

Subtask #1
6.0 / 6.0

# Verdict Execution time Memory Grader output
1 Correct 0 ms 204 KB Output is correct
2 Correct 1 ms 204 KB Output is correct

Subtask #2
30.0 / 30.0

# Verdict Execution time Memory Grader output
1 Correct 0 ms 204 KB Output is correct
2 Correct 1 ms 204 KB Output is correct
3 Correct 1 ms 308 KB Output is correct
4 Correct 1 ms 204 KB Output is correct
5 Correct 1 ms 332 KB Output is correct
6 Correct 1 ms 204 KB Output is correct
7 Correct 1 ms 204 KB Output is correct
8 Correct 1 ms 332 KB Output is correct
9 Correct 1 ms 204 KB Output is correct
10 Correct 1 ms 204 KB Output is correct
11 Correct 0 ms 204 KB Output is correct

Subtask #3
15.0 / 15.0

# Verdict Execution time Memory Grader output
1 Correct 0 ms 204 KB Output is correct
2 Correct 1 ms 204 KB Output is correct
3 Correct 1 ms 308 KB Output is correct
4 Correct 1 ms 204 KB Output is correct
5 Correct 1 ms 332 KB Output is correct
6 Correct 1 ms 204 KB Output is correct
7 Correct 1 ms 204 KB Output is correct
8 Correct 1 ms 332 KB Output is correct
9 Correct 1 ms 204 KB Output is correct
10 Correct 1 ms 204 KB Output is correct
11 Correct 0 ms 204 KB Output is correct
12 Correct 1 ms 588 KB Output is correct
13 Correct 1 ms 564 KB Output is correct
14 Correct 1 ms 588 KB Output is correct
15 Correct 1 ms 588 KB Output is correct
16 Correct 1 ms 588 KB Output is correct
17 Correct 1 ms 588 KB Output is correct
18 Correct 1 ms 460 KB Output is correct
19 Correct 1 ms 568 KB Output is correct
20 Correct 1 ms 588 KB Output is correct

Subtask #4
49.0 / 49.0

# Verdict Execution time Memory Grader output
1 Correct 0 ms 204 KB Output is correct
2 Correct 1 ms 204 KB Output is correct
3 Correct 1 ms 308 KB Output is correct
4 Correct 1 ms 204 KB Output is correct
5 Correct 1 ms 332 KB Output is correct
6 Correct 1 ms 204 KB Output is correct
7 Correct 1 ms 204 KB Output is correct
8 Correct 1 ms 332 KB Output is correct
9 Correct 1 ms 204 KB Output is correct
10 Correct 1 ms 204 KB Output is correct
11 Correct 0 ms 204 KB Output is correct
12 Correct 1 ms 588 KB Output is correct
13 Correct 1 ms 564 KB Output is correct
14 Correct 1 ms 588 KB Output is correct
15 Correct 1 ms 588 KB Output is correct
16 Correct 1 ms 588 KB Output is correct
17 Correct 1 ms 588 KB Output is correct
18 Correct 1 ms 460 KB Output is correct
19 Correct 1 ms 568 KB Output is correct
20 Correct 1 ms 588 KB Output is correct
21 Correct 6 ms 3660 KB Output is correct
22 Correct 6 ms 4172 KB Output is correct
23 Correct 5 ms 4792 KB Output is correct
24 Correct 33 ms 31732 KB Output is correct
25 Correct 36 ms 31692 KB Output is correct
26 Correct 33 ms 31640 KB Output is correct
27 Correct 37 ms 31420 KB Output is correct
28 Correct 23 ms 17872 KB Output is correct