Submission #20171

#	Submission time	Handle	Problem	Language	Result	Execution time	Memory
20171	2016-03-01T05:51:33 Z	sui	괄호 (kriii4_R)	C++14	8 / 100	128 ms	48604 KB

R

#define _CRT_SECURE_NO_WARNINGS // scanf(), gets() (needed for Visual C++)

//#define NDEBUG
#include <cassert>

#include <iostream>
#include <cstdio>
#include <cstring>
#include <cmath>
#include <algorithm>
#include <functional>
#include <string>
#include <vector>

#include <queue>
#include <set>
#include <map>
#include <unordered_map>
#include <stack>
#include <deque>


using namespace std;

#define MEMSET(x, WITH) memset(x, (WITH), sizeof(x))
#define FOR(i, E) for(int i=0; i<(E); i++)
#define REP(i, LO, HI) for(int i=(LO); i<=(HI); i++)

#define GETINT(x) scanf("%d", &x)
#define GETDBL(x) scanf("%lf", &x)
#define GETSTR(x) scanf("%s", x)
#define NEWINT(x) int x; scanf("%d", &x)
#define NEWDBL(x) double x; scanf("%lf", &x)
#define NEWLN putchar('\n')

typedef long long ll;

const ll MOD = 1000000007;
//const double PI = atan(1) * 4;

#ifdef _WIN32
#define popcnt __popcnt
#else
#define popcnt __builtin_popcount
#endif





const int SZ = 2000333;

ll inv[SZ];
ll fac[SZ];
ll invfac[SZ];

void precalc() {
	inv[1] = 1;
	for (int x=2; x<SZ; x++) {
		ll q = MOD / x;
		ll r = MOD % x;

		q = MOD - q;
		inv[x] = q * inv[r] % MOD;
	}

	fac[0] = 1;
	for (int x=1; x<SZ; x++) fac[x] = fac[x-1] * x % MOD;

	invfac[0] = 1;
	for (int x=1; x<SZ; x++) invfac[x] = invfac[x-1] * inv[x] % MOD;
}

ll getCatalanNumber(int n) {
	return fac[2*n] * invfac[n] % MOD * invfac[n+1] % MOD;
}







int main() {
	precalc();

	int N, K;
	cin >> N >> K;



	ll sum = 1;
	ll a = 1;

	for (int i=2; i<=N; i++) {
		if (i&1) {
			sum = (sum + sum - a + MOD) % MOD;
			a = getCatalanNumber(i/2 + 1);
		} 
		else {
			sum = (sum + sum) % MOD;
		}
	}


	cout << sum << endl;


	return 0;
}

Subtask #1

8.0 / 8.0

#	Verdict	Execution time	Memory	Grader output
1	Correct	115 ms	48604 KB	Output is correct
2	Correct	116 ms	48604 KB	Output is correct
3	Correct	116 ms	48604 KB	Output is correct
4	Correct	113 ms	48604 KB	Output is correct
5	Correct	99 ms	48604 KB	Output is correct
6	Correct	113 ms	48604 KB	Output is correct
7	Correct	110 ms	48604 KB	Output is correct
8	Correct	111 ms	48604 KB	Output is correct
9	Correct	111 ms	48604 KB	Output is correct
10	Correct	110 ms	48604 KB	Output is correct
11	Correct	99 ms	48604 KB	Output is correct
12	Correct	116 ms	48604 KB	Output is correct
13	Correct	115 ms	48604 KB	Output is correct
14	Correct	108 ms	48604 KB	Output is correct
15	Correct	112 ms	48604 KB	Output is correct
16	Correct	104 ms	48604 KB	Output is correct
17	Correct	111 ms	48604 KB	Output is correct
18	Correct	114 ms	48604 KB	Output is correct
19	Correct	118 ms	48604 KB	Output is correct
20	Correct	128 ms	48604 KB	Output is correct

Subtask #2

0.0 / 92.0

#	Verdict	Execution time	Memory	Grader output
1	Incorrect	119 ms	48604 KB	Output isn't correct
2	Halted	0 ms	0 KB	-