Submission #291669

# Submission time Handle Problem Language Result Execution time Memory
291669 2020-09-05T15:45:11 Z penguinhacker Zapina (COCI20_zapina) C++17
110 / 110
640 ms 512 KB
#include <bits/stdc++.h>
using namespace std;

#define ll long long
#define ar array

const int MOD=1e9+7;
int binPow(ll b, int p=MOD-2) {
	ll res=1;
	while(p>0) {
		if (p&1) res=res*b%MOD;
		b=b*b%MOD;
		p>>=1;
	}
	return res;
}

vector<ll> f={1}, iF={1};
ll C(int a, int b) {
	if (a<0||b<0||b>a) return 0;
	assert(a<=(int)5e6);
	while(f.size()<=a) {
		int x=f.size();
		f.push_back(f.back()*x%MOD);
		iF.push_back(iF.back()*binPow(x)%MOD);
	}
	return f[a]*iF[b]%MOD*iF[a-b]%MOD;
}

int n;
vector<vector<ll>> dp, last;

int main() {
	ios::sync_with_stdio(0);
	cin.tie(0);

	cin >> n;
	dp.assign(n+1, vector<ll>(2, 0));
	dp[0][0]=1;
	for (int i=1; i<=n; ++i) {
		last=dp;
		for (int j=i; j<=n; ++j) {
			dp[j][1]=(dp[j][1]+(last[j-i][0]+last[j-i][1])*C(n-j+i, i))%MOD;
		}
		for (int j=1; j<=n; ++j) {
			for (int k=1; k<=j; ++k) if (k!=i) {
				dp[j][1]=(dp[j][1]+last[j-k][1]*C(n-j+k, k))%MOD;
				dp[j][0]=(dp[j][0]+last[j-k][0]*C(n-j+k, k))%MOD;
			}
		}
	}
	cout << dp[n][1] << "\n";
	return 0;
}

Compilation message

zapina.cpp: In function 'long long int C(int, int)':
zapina.cpp:22:16: warning: comparison of integer expressions of different signedness: 'std::vector<long long int>::size_type' {aka 'long unsigned int'} and 'int' [-Wsign-compare]
   22 |  while(f.size()<=a) {
      |        ~~~~~~~~^~~
# Verdict Execution time Memory Grader output
1 Correct 0 ms 384 KB Output is correct
2 Correct 0 ms 384 KB Output is correct
3 Correct 1 ms 384 KB Output is correct
4 Correct 0 ms 384 KB Output is correct
5 Correct 1 ms 384 KB Output is correct
# Verdict Execution time Memory Grader output
1 Correct 0 ms 384 KB Output is correct
2 Correct 0 ms 384 KB Output is correct
3 Correct 1 ms 384 KB Output is correct
4 Correct 0 ms 384 KB Output is correct
5 Correct 1 ms 384 KB Output is correct
6 Correct 1 ms 384 KB Output is correct
7 Correct 0 ms 384 KB Output is correct
8 Correct 1 ms 512 KB Output is correct
9 Correct 1 ms 384 KB Output is correct
10 Correct 1 ms 384 KB Output is correct
11 Correct 0 ms 384 KB Output is correct
12 Correct 1 ms 384 KB Output is correct
13 Correct 1 ms 384 KB Output is correct
14 Correct 1 ms 384 KB Output is correct
15 Correct 1 ms 384 KB Output is correct
16 Correct 1 ms 384 KB Output is correct
# Verdict Execution time Memory Grader output
1 Correct 0 ms 384 KB Output is correct
2 Correct 0 ms 384 KB Output is correct
3 Correct 1 ms 384 KB Output is correct
4 Correct 0 ms 384 KB Output is correct
5 Correct 1 ms 384 KB Output is correct
6 Correct 1 ms 384 KB Output is correct
7 Correct 0 ms 384 KB Output is correct
8 Correct 1 ms 512 KB Output is correct
9 Correct 1 ms 384 KB Output is correct
10 Correct 1 ms 384 KB Output is correct
11 Correct 0 ms 384 KB Output is correct
12 Correct 1 ms 384 KB Output is correct
13 Correct 1 ms 384 KB Output is correct
14 Correct 1 ms 384 KB Output is correct
15 Correct 1 ms 384 KB Output is correct
16 Correct 1 ms 384 KB Output is correct
17 Correct 294 ms 504 KB Output is correct
18 Correct 3 ms 384 KB Output is correct
19 Correct 65 ms 384 KB Output is correct
20 Correct 1 ms 384 KB Output is correct
21 Correct 388 ms 384 KB Output is correct
22 Correct 44 ms 384 KB Output is correct
23 Correct 4 ms 384 KB Output is correct
24 Correct 83 ms 384 KB Output is correct
25 Correct 56 ms 384 KB Output is correct
26 Correct 112 ms 308 KB Output is correct
27 Correct 556 ms 384 KB Output is correct
28 Correct 564 ms 504 KB Output is correct
29 Correct 567 ms 508 KB Output is correct
30 Correct 571 ms 504 KB Output is correct
31 Correct 577 ms 504 KB Output is correct
32 Correct 583 ms 384 KB Output is correct
33 Correct 588 ms 504 KB Output is correct
34 Correct 597 ms 384 KB Output is correct
35 Correct 640 ms 504 KB Output is correct
36 Correct 614 ms 384 KB Output is correct
37 Correct 598 ms 384 KB Output is correct