oj.uz

Submission #308920

# Submission time Handle Problem Language Result Execution time Memory
308920 2020-10-02T09:47:13 Z arnold518 Kangaroo (CEOI16_kangaroo) C++14
51 / 100
 2 ms 1664 KB 
#include <bits/stdc++.h>
using namespace std;

typedef long long ll;
typedef pair<int, int> pii;
typedef pair<ll, ll> pll;

const int MAXN = 400;
const ll MOD = 1e9+7;

int N, S, E;

ll dp[MAXN+10][MAXN+10];

ll solve(int pos, int comp)
{
	if(pos==N+1)
	{
		if(comp==1) return 1;
		else return 0;
	}
	ll &ret=dp[pos][comp];
	if(ret!=-1) return ret;

	ret=0;

	if(pos==S)
	{
		ret+=solve(pos+1, comp);
		ret+=solve(pos+1, comp+1);
	}
	else if(pos==E)
	{
		ret+=solve(pos+1, comp);
		ret+=solve(pos+1, comp+1);
	}
	else if(pos<S)
	{
		if(comp>=2) ret+=(comp-1)*solve(pos+1, comp-1);
		ret+=(comp+1)*solve(pos+1, comp+1);
	}
	else if(pos<E)
	{
		if(comp>=2) ret+=(comp-1)*solve(pos+1, comp-1);
		ret+=(comp)*solve(pos+1, comp+1);	
	}
	else
	{
		if(comp>=2) ret+=(comp-1)*solve(pos+1, comp-1);
		ret+=(comp-1)*solve(pos+1, comp+1);		
	}
	ret%=MOD;
	//printf("%d %d : %lld\n", pos, comp, ret);
	return ret;
}

int main()
{
	scanf("%d%d%d", &N, &S, &E); if(S>E) swap(S, E);
	memset(dp, -1, sizeof(dp));
	printf("%lld\n", solve(1, 0));

}

Compilation message

kangaroo.cpp: In function 'int main()':
kangaroo.cpp:59:7: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   59 |  scanf("%d%d%d", &N, &S, &E); if(S>E) swap(S, E);
      |  ~~~~~^~~~~~~~~~~~~~~~~~~~~~

Subtask #1
6.0 / 6.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 1664 KB Output is correct
2 Correct 1 ms 1664 KB Output is correct

Subtask #2
30.0 / 30.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 1664 KB Output is correct
2 Correct 1 ms 1664 KB Output is correct
3 Correct 1 ms 1664 KB Output is correct
4 Correct 1 ms 1664 KB Output is correct
5 Correct 2 ms 1664 KB Output is correct
6 Correct 1 ms 1664 KB Output is correct
7 Correct 1 ms 1664 KB Output is correct
8 Correct 1 ms 1664 KB Output is correct
9 Correct 1 ms 1664 KB Output is correct
10 Correct 1 ms 1664 KB Output is correct
11 Correct 1 ms 1664 KB Output is correct

Subtask #3
15.0 / 15.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 1664 KB Output is correct
2 Correct 1 ms 1664 KB Output is correct
3 Correct 1 ms 1664 KB Output is correct
4 Correct 1 ms 1664 KB Output is correct
5 Correct 2 ms 1664 KB Output is correct
6 Correct 1 ms 1664 KB Output is correct
7 Correct 1 ms 1664 KB Output is correct
8 Correct 1 ms 1664 KB Output is correct
9 Correct 1 ms 1664 KB Output is correct
10 Correct 1 ms 1664 KB Output is correct
11 Correct 1 ms 1664 KB Output is correct
12 Correct 2 ms 1664 KB Output is correct
13 Correct 2 ms 1664 KB Output is correct
14 Correct 1 ms 1664 KB Output is correct
15 Correct 2 ms 1664 KB Output is correct
16 Correct 2 ms 1664 KB Output is correct
17 Correct 1 ms 1664 KB Output is correct
18 Correct 2 ms 1664 KB Output is correct
19 Correct 1 ms 1664 KB Output is correct
20 Correct 2 ms 1664 KB Output is correct

Subtask #4
0 / 49.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 1664 KB Output is correct
2 Correct 1 ms 1664 KB Output is correct
3 Correct 1 ms 1664 KB Output is correct
4 Correct 1 ms 1664 KB Output is correct
5 Correct 2 ms 1664 KB Output is correct
6 Correct 1 ms 1664 KB Output is correct
7 Correct 1 ms 1664 KB Output is correct
8 Correct 1 ms 1664 KB Output is correct
9 Correct 1 ms 1664 KB Output is correct
10 Correct 1 ms 1664 KB Output is correct
11 Correct 1 ms 1664 KB Output is correct
12 Correct 2 ms 1664 KB Output is correct
13 Correct 2 ms 1664 KB Output is correct
14 Correct 1 ms 1664 KB Output is correct
15 Correct 2 ms 1664 KB Output is correct
16 Correct 2 ms 1664 KB Output is correct
17 Correct 1 ms 1664 KB Output is correct
18 Correct 2 ms 1664 KB Output is correct
19 Correct 1 ms 1664 KB Output is correct
20 Correct 2 ms 1664 KB Output is correct
21 Incorrect 2 ms 1664 KB Output isn't correct
22 Halted 0 ms 0 KB -