Submission #712829

# Submission time Handle Problem Language Result Execution time Memory
712829 2023-03-20T08:10:50 Z ymm Asceticism (JOI18_asceticism) C++17
100 / 100
380 ms 5068 KB
#include <bits/stdc++.h>
#define Loop(x,l,r) for (ll x = (l); x < (ll)(r); ++x)
#define LoopR(x,l,r) for (ll x = (r)-1; x >= (ll)(l); --x)
typedef long long ll;
typedef std::pair<int, int> pii;
typedef std::pair<ll , ll > pll;
using namespace std;

const int mod = 1e9+7;

ll pw(ll x, ll y)
{
	ll ans = 1;
	while (y) {
		if (y%2)
			ans = ans*x % mod;
		x = x*x % mod;
		y /= 2;
	}
	return ans;
}
ll inv(ll x) { return pw(x, mod-2); }

const int N = 100'010;
ll fct[N], fcti[N];

void init()
{
	fct[0] = 1;
	Loop (i,1,N)
		fct[i] = fct[i-1] * i % mod;
	fcti[N-1] = inv(fct[N-1]);
	LoopR (i,1,N)
		fcti[i-1] = fcti[i] * i % mod;
}

ll C(int n, int r)
{
	if (r < 0 || n < r)
		return 0;
	return fct[n] * fcti[r] % mod * fcti[n-r] % mod;
}

typedef vector<int> poly;
typedef unsigned long long ull;

#define MOD(x) ((x) >= mod? (x) - mod: x)

template<int n>
void karatsuba(int *__restrict__ a, int *__restrict__ b, int *__restrict__ ans, int *__restrict__ tmp, int rem)
{
	if (rem <= 0) {
		fill(ans, ans+2*n, 0);
		return;
	}
	if constexpr (n <= 16) {
		static ull ansl[2*n];
		Loop (i,0,2*n)
			ansl[i] = 0;
		Loop (i,0,n) Loop (j,0,n)
			ansl[i+j] += (ull)a[i] * b[j];
		Loop (i,0,2*n)
			ans[i] = ansl[i] % mod;
		return;
	}
	Loop (i,0,n) {
		tmp[i] = a[i];
		tmp[i+n] = b[i];
	}
	Loop (i,0,n/2)
		a[i+n/2] = b[i];
	karatsuba<n/2>(a, a+n/2, ans, b, rem);
	Loop (i,0,n/2) {
		a[i] = tmp[i+n/2];
		a[i+n/2] = tmp[i+n+n/2];
	}
	karatsuba<n/2>(a, a+n/2, ans+n, b, rem - n/2);
	Loop (i,0,n/2) {
		a[i] = MOD(tmp[i] + tmp[i+n/2]);
		a[i+n/2] = MOD(tmp[i+n] + tmp[i+n+n/2]);
	}
	karatsuba<n/2>(a, a+n/2, b, tmp, rem - n/2);
	Loop (i,0,n)
		b[i] = MOD(MOD(b[i] + mod - ans[i]) + mod - ans[i+n]);
	Loop (i,0,n)
		ans[i+n/2] = MOD(ans[i+n/2] + b[i]);
}

vector<int> stir;

void init_stir(int m)
{
	const int M = 131072;
	poly A(M), B(M);
	Loop (i,0,N) {
		A[i] = pw(i, m) * fcti[i] % mod;
		B[i] = i%2? mod-fcti[i]: fcti[i];
	}
	stir.resize(2*M);
	vector<int> tmp(2*M);
	karatsuba<M>(&A[0], &B[0], &stir[0], &tmp[0], N);
	stir.resize(N);
	Loop (i,0,N)
		stir[i] = fct[i] * stir[i] % mod;
}

int main()
{
	cin.tie(0) -> sync_with_stdio(false);
	ll a, b;
	cin >> b >> a;
	init();
	init_stir(b);
	ll ans = 0;
	Loop (x,0,a) {
		ll dard = stir[a-x] * C(b-a+x, x) % mod;
		ans += x%2? -dard: dard;
	}
	ans = (ans%mod+mod) % mod;
	cout << ans << '\n';
}

Compilation message

asceticism.cpp: In instantiation of 'void karatsuba(int*, int*, int*, int*, int) [with int n = 1]':
asceticism.cpp:72:16:   recursively required from 'void karatsuba(int*, int*, int*, int*, int) [with int n = 65536]'
asceticism.cpp:72:16:   required from 'void karatsuba(int*, int*, int*, int*, int) [with int n = 131072]'
asceticism.cpp:101:49:   required from here
asceticism.cpp:72:16: warning: passing argument 1 to 'restrict'-qualified parameter aliases with argument 2 [-Wrestrict]
   72 |  karatsuba<n/2>(a, a+n/2, ans, b, rem);
      |  ~~~~~~~~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~
asceticism.cpp:77:16: warning: passing argument 1 to 'restrict'-qualified parameter aliases with argument 2 [-Wrestrict]
   77 |  karatsuba<n/2>(a, a+n/2, ans+n, b, rem - n/2);
      |  ~~~~~~~~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
asceticism.cpp:82:16: warning: passing argument 1 to 'restrict'-qualified parameter aliases with argument 2 [-Wrestrict]
   82 |  karatsuba<n/2>(a, a+n/2, b, tmp, rem - n/2);
      |  ~~~~~~~~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~
asceticism.cpp: In instantiation of 'void karatsuba(int*, int*, int*, int*, int) [with int n = 0]':
asceticism.cpp:72:16:   recursively required from 'void karatsuba(int*, int*, int*, int*, int) [with int n = 65536]'
asceticism.cpp:72:16:   required from 'void karatsuba(int*, int*, int*, int*, int) [with int n = 131072]'
asceticism.cpp:101:49:   required from here
asceticism.cpp:72:16: warning: passing argument 1 to 'restrict'-qualified parameter aliases with argument 2 [-Wrestrict]
   72 |  karatsuba<n/2>(a, a+n/2, ans, b, rem);
      |  ~~~~~~~~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~
asceticism.cpp:77:16: warning: passing argument 1 to 'restrict'-qualified parameter aliases with argument 2 [-Wrestrict]
   77 |  karatsuba<n/2>(a, a+n/2, ans+n, b, rem - n/2);
      |  ~~~~~~~~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
asceticism.cpp:82:16: warning: passing argument 1 to 'restrict'-qualified parameter aliases with argument 2 [-Wrestrict]
   82 |  karatsuba<n/2>(a, a+n/2, b, tmp, rem - n/2);
      |  ~~~~~~~~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~
# Verdict Execution time Memory Grader output
1 Correct 332 ms 4968 KB Output is correct
2 Correct 344 ms 4968 KB Output is correct
3 Correct 319 ms 4972 KB Output is correct
4 Correct 339 ms 4968 KB Output is correct
5 Correct 320 ms 4948 KB Output is correct
6 Correct 318 ms 4968 KB Output is correct
7 Correct 319 ms 4968 KB Output is correct
8 Correct 309 ms 4980 KB Output is correct
9 Correct 325 ms 4972 KB Output is correct
10 Correct 308 ms 4972 KB Output is correct
# Verdict Execution time Memory Grader output
1 Correct 332 ms 4968 KB Output is correct
2 Correct 344 ms 4968 KB Output is correct
3 Correct 319 ms 4972 KB Output is correct
4 Correct 339 ms 4968 KB Output is correct
5 Correct 320 ms 4948 KB Output is correct
6 Correct 318 ms 4968 KB Output is correct
7 Correct 319 ms 4968 KB Output is correct
8 Correct 309 ms 4980 KB Output is correct
9 Correct 325 ms 4972 KB Output is correct
10 Correct 308 ms 4972 KB Output is correct
11 Correct 325 ms 5068 KB Output is correct
12 Correct 309 ms 4984 KB Output is correct
13 Correct 309 ms 5068 KB Output is correct
14 Correct 316 ms 4968 KB Output is correct
15 Correct 310 ms 4984 KB Output is correct
16 Correct 319 ms 4964 KB Output is correct
17 Correct 309 ms 4948 KB Output is correct
18 Correct 318 ms 5068 KB Output is correct
19 Correct 315 ms 4976 KB Output is correct
20 Correct 310 ms 4972 KB Output is correct
# Verdict Execution time Memory Grader output
1 Correct 332 ms 4968 KB Output is correct
2 Correct 344 ms 4968 KB Output is correct
3 Correct 319 ms 4972 KB Output is correct
4 Correct 339 ms 4968 KB Output is correct
5 Correct 320 ms 4948 KB Output is correct
6 Correct 318 ms 4968 KB Output is correct
7 Correct 319 ms 4968 KB Output is correct
8 Correct 309 ms 4980 KB Output is correct
9 Correct 325 ms 4972 KB Output is correct
10 Correct 308 ms 4972 KB Output is correct
11 Correct 325 ms 5068 KB Output is correct
12 Correct 309 ms 4984 KB Output is correct
13 Correct 309 ms 5068 KB Output is correct
14 Correct 316 ms 4968 KB Output is correct
15 Correct 310 ms 4984 KB Output is correct
16 Correct 319 ms 4964 KB Output is correct
17 Correct 309 ms 4948 KB Output is correct
18 Correct 318 ms 5068 KB Output is correct
19 Correct 315 ms 4976 KB Output is correct
20 Correct 310 ms 4972 KB Output is correct
21 Correct 317 ms 4968 KB Output is correct
22 Correct 315 ms 4976 KB Output is correct
23 Correct 326 ms 4980 KB Output is correct
24 Correct 305 ms 4984 KB Output is correct
25 Correct 316 ms 5068 KB Output is correct
26 Correct 315 ms 4948 KB Output is correct
27 Correct 315 ms 4948 KB Output is correct
28 Correct 325 ms 4980 KB Output is correct
29 Correct 316 ms 4968 KB Output is correct
30 Correct 331 ms 4972 KB Output is correct
# Verdict Execution time Memory Grader output
1 Correct 332 ms 4968 KB Output is correct
2 Correct 344 ms 4968 KB Output is correct
3 Correct 319 ms 4972 KB Output is correct
4 Correct 339 ms 4968 KB Output is correct
5 Correct 320 ms 4948 KB Output is correct
6 Correct 318 ms 4968 KB Output is correct
7 Correct 319 ms 4968 KB Output is correct
8 Correct 309 ms 4980 KB Output is correct
9 Correct 325 ms 4972 KB Output is correct
10 Correct 308 ms 4972 KB Output is correct
11 Correct 325 ms 5068 KB Output is correct
12 Correct 309 ms 4984 KB Output is correct
13 Correct 309 ms 5068 KB Output is correct
14 Correct 316 ms 4968 KB Output is correct
15 Correct 310 ms 4984 KB Output is correct
16 Correct 319 ms 4964 KB Output is correct
17 Correct 309 ms 4948 KB Output is correct
18 Correct 318 ms 5068 KB Output is correct
19 Correct 315 ms 4976 KB Output is correct
20 Correct 310 ms 4972 KB Output is correct
21 Correct 317 ms 4968 KB Output is correct
22 Correct 315 ms 4976 KB Output is correct
23 Correct 326 ms 4980 KB Output is correct
24 Correct 305 ms 4984 KB Output is correct
25 Correct 316 ms 5068 KB Output is correct
26 Correct 315 ms 4948 KB Output is correct
27 Correct 315 ms 4948 KB Output is correct
28 Correct 325 ms 4980 KB Output is correct
29 Correct 316 ms 4968 KB Output is correct
30 Correct 331 ms 4972 KB Output is correct
31 Correct 351 ms 4948 KB Output is correct
32 Correct 380 ms 4968 KB Output is correct
33 Correct 333 ms 4948 KB Output is correct
34 Correct 350 ms 4984 KB Output is correct
35 Correct 345 ms 4948 KB Output is correct
36 Correct 344 ms 4984 KB Output is correct
37 Correct 356 ms 4948 KB Output is correct
38 Correct 346 ms 4968 KB Output is correct
39 Correct 329 ms 4968 KB Output is correct
40 Correct 320 ms 4976 KB Output is correct