Submission 834 | MatCom Online Grader

Id	Date	User	Problem	Result	Time	Mem	Lang
834	15/05/2013 23:00:23	leandro	B - Palíndromo	Accepted	328	1.4 KiB	GNU G++ 5.1.0

Code

/*
username: leandro
*/
#include <cstdio>
#include <vector>
#include <algorithm>
#include <iostream>
#include <cstring>
#include <cmath>
#include <cstdlib>
#include <complex>
#include <set>
#include <map>
#include <sstream>
#include <queue>
#include <stack>

using namespace std;

//////////////////////////////////////
typedef long long i64;
typedef complex<double> pnt;
typedef pair<int, int> pii;
typedef vector<int> vi;
//////////////////////////////////////
const int oo = 1 << 30;
const double PI = M_PI;
const double EPS = 1e-15;
//////////////////////////////////////
#define F first
#define S second
#define foreach(i, u) \
		for (typeof(u.begin()) i = u.begin(); i != u.end(); i++)
#define REP(i, n) \
		for (int i = 0; i < (n); i++)
#define FOR(i, n) \
		for (int i = 1; i <= (n); i++)
//////////////////////////////////////
#define DEBUG(x) \
		cout << #x << " = " << x << endl

const i64 MOD = 1000000007LL;

int test;
i64 n;

i64 mulMod(i64 a, i64 b)
{
	if (!b)
		return 0;
	if (b % 2)
		return (a + mulMod(a, b - 1)) % MOD;
	i64 x = mulMod(a, b / 2);
	return (x + x) % MOD;
}

i64 powMod(i64 x, i64 m)
{
	if (!m)
		return 1;
	if (m % 2)
		return mulMod(x, powMod(x, m - 1));
	i64 t = powMod(x, m / 2);
	return mulMod(t, t);
}

int main()
{
	cin.sync_with_stdio(false);

for (cin >> test; test; test--)
	{
		cin >> n;
		i64 even = 0, odd = 0;
		if (n > 1)
		{
			even = powMod(26, (n / 2) + 1);
			even = (even - 1 + MOD) %  MOD;
			even = mulMod(even, powMod(25, MOD - 2));
			even = (even - 1 + MOD) %  MOD;
		}
		odd = powMod(26, (n + 1) / 2);
		odd = (odd - 1 + MOD) %   MOD;
		odd = mulMod(odd, powMod(25, MOD - 2));
		odd = mulMod(26, odd);
		cout << (even + odd) % MOD << endl;
	}

return 0;
}

Judgement Details

Test 01: 0.047 0.031 1388K ok
Test 02: 0.360 0.328 1436K ok
Test 03: 0.060 0.062 1392K ok
Test 04: 0.083 0.078 1388K ok
Test 05: 0.105 0.078 1392K ok
Test 06: 0.188 0.109 1392K ok
Test 07: 0.160 0.140 1408K ok
Test 08: 0.180 0.172 1388K ok
Test 09: 0.244 0.203 1408K ok
Test 10: 0.235 0.218 1404K ok
Accepted

Matcom Online Grader