Submission #14566066
Source Code Expand
Copy
#include <bits/stdc++.h>
using namespace std;
using ll = long long;
using ld = long double;
using vi = vector<int>;
using vvi = vector<vi>;
using vll = vector<ll>;
using vvll = vector<vll>;
using vb = vector<bool>;
using vs = vector<string>;
using vld = vector<ld>;
using vvld = vector<vld>;
typedef pair<ll, ll> P;
#define bit(n) (1LL << (n))
//#define int long long
#define all(v) v.begin(), v.end()
#define rep(i, n) for (ll i = 0; i < n; i++)
#define REP(i, n) for (ll i = 1; i < n; i++)
#define FOR(i, a, b) for (ll i = (a); i < (b); i++)
#define FORm(i, m) for (auto i = m.begin(); i != m.end(); i++)
template <class T>
inline void chmax(T& a, T b) {
a = std::max(a, b);
}
template <class T>
inline void chmin(T& a, T b) {
a = std::min(a, b);
}
#define mod (ll)(1e9 + 7)
// #define mod (998244353ll)
const long long INF = 1LL << 60;
// #define mod (ll)(1e9 + 7)
template <ll ModVal>
struct ModInt {
ll x;
ModInt(ll _x = 0) : x((_x % ModVal + ModVal) % ModVal) {
}
ModInt operator-() const {
return ModInt(-x);
}
ModInt& operator+=(const ModInt a) {
x += a.x;
if (x >= ModVal)
x -= ModVal;
return *this;
}
ModInt& operator-=(const ModInt a) {
x = x + ModVal - a.x;
if (x >= ModVal)
x -= ModVal;
return *this;
}
ModInt& operator*=(const ModInt a) {
x *= a.x;
x %= ModVal;
return *this;
}
ll ext_gcd(ll a, ll b, ll& x, ll& y) {
if (b == 0) {
x = 1;
y = 0;
return a;
}
ll tmp = a / b;
ll d = ext_gcd(b, a - b * tmp, y, x);
y -= tmp * x;
return d;
}
// 逆元
ModInt inv() {
ll u, v;
ext_gcd(x, ModVal, u, v);
return ModInt(u);
}
ModInt inv(const ModInt a) {
ll u, v;
ext_gcd(a.x, ModVal, u, v);
return ModInt(u);
}
ModInt& operator/=(const ModInt a) {
return (*this) *= inv(a);
}
ModInt operator+(const ModInt a) const {
ModInt retval(*this);
return retval += a;
}
ModInt operator-(const ModInt a) const {
ModInt retval(*this);
return retval -= a;
}
ModInt operator*(const ModInt a) const {
ModInt retval(*this);
return retval *= a;
}
ModInt operator/(const ModInt a) const {
ModInt retval(*this);
return retval /= a;
}
ModInt pow(ll n) {
ModInt ans(1);
while (n) {
if (n & 1)
ans = ans * x;
*this = (*this) * (*this);
n = n >> 1;
}
return ans;
}
constexpr const ll& value() {
return this->x;
}
};
template <ll ModVal>
ostream& operator<<(ostream& os, const ModInt<ModVal>& a) {
os << a.x;
return os;
}
using mint = ModInt<mod>;
template <typename T>
class Combination {
public:
Combination(ll _max_n) : max_n(_max_n), factional(max_n + 1), inv(max_n + 1) {
factional[0] = 1;
inv[0] = 1;
for (ll i = 0; i < max_n; i++) {
factional[i + 1] = factional[i] * (i + 1); // n!(mod M)
inv[i + 1] = inv[i] / (i + 1); // k!^(M-2) (mod M)
}
}
// nCk
T choose(ll n, ll k) {
if (n == 0 && k == 0)
return 1;
if (n < k || n < 0)
return 0;
T tmp = inv[n - k] * inv[k];
return tmp * factional[n];
}
T permutation(ll n, ll k) {
if (n - k < 0) {
return 0;
}
return factional[n] / factional[n - k];
}
private:
const ll max_n;
std::vector<T> factional;
std::vector<T> inv;
};
using Comb = Combination<mint>;
using vm = vector<mint>;
using vvm = vector<vm>;
using vvvm = vector<vvm>;
signed main() {
cin.tie(0);
ios::sync_with_stdio(false);
cout << fixed << setprecision(20);
ll k;
cin >> k;
string s;
cin >> s;
// 最終的な文字列の長さ
ll n = s.size() + k;
#if 0
vvll dp(n + 1, vll(n + 1));
dp[0][0] = 1;
rep(i, n) {
rep(j, n) {
dp[i + 1][j] += dp[i][j] * 25;
dp[i + 1][j + 1] += dp[i][j];
}
}
ll ans = 0;
FOR(i, n - k, n + 1) {
ans += dp[n][i];
}
cout << ans << endl;
#endif
vm pow25(n + 10);
pow25[0] = 1;
rep(i, n + 1) {
pow25[i + 1] = pow25[i] * 25;
}
Comb C(n + 10);
mint ans = 0;
FOR(i, n - k, n + 1) {
mint ptn = 0;
ptn = C.choose(n, i) * pow25[n - i];
ans += ptn;
}
cout << ans << endl;
return 0;
}
Submission Info
Submission Time |
|
Task |
F - Strivore |
User |
spiralray |
Language |
C++ (GCC 9.2.1) |
Score |
600 |
Code Size |
4212 Byte |
Status |
AC |
Exec Time |
455 ms |
Memory |
51228 KB |
Judge Result
Set Name |
Sample |
Subtask1 |
Score / Max Score |
0 / 0 |
600 / 600 |
Status |
|
|
Set Name |
Test Cases |
Sample |
sample_01.txt, sample_02.txt |
Subtask1 |
sample_01.txt, sample_02.txt, sub1_01.txt, sub1_02.txt, sub1_03.txt, sub1_04.txt, sub1_05.txt, sub1_06.txt, sub1_07.txt, sub1_08.txt, sub1_09.txt, sub1_10.txt, sub1_11.txt, sub1_12.txt, sub1_13.txt, sub1_14.txt, sub1_15.txt, sub1_16.txt, sub1_17.txt, sub1_18.txt, sub1_19.txt, sub1_20.txt, sub1_21.txt, sub1_22.txt, sub1_23.txt, sub1_24.txt, sub1_25.txt, sub1_26.txt, sub1_27.txt, sub1_28.txt |
Case Name |
Status |
Exec Time |
Memory |
sample_01.txt |
AC |
7 ms |
3504 KB |
sample_02.txt |
AC |
10 ms |
3912 KB |
sub1_01.txt |
AC |
444 ms |
51180 KB |
sub1_02.txt |
AC |
447 ms |
51228 KB |
sub1_03.txt |
AC |
445 ms |
51148 KB |
sub1_04.txt |
AC |
455 ms |
51144 KB |
sub1_05.txt |
AC |
40 ms |
7280 KB |
sub1_06.txt |
AC |
151 ms |
20280 KB |
sub1_07.txt |
AC |
176 ms |
22928 KB |
sub1_08.txt |
AC |
219 ms |
27644 KB |
sub1_09.txt |
AC |
216 ms |
27680 KB |
sub1_10.txt |
AC |
220 ms |
27576 KB |
sub1_11.txt |
AC |
147 ms |
18140 KB |
sub1_12.txt |
AC |
91 ms |
12072 KB |
sub1_13.txt |
AC |
229 ms |
26596 KB |
sub1_14.txt |
AC |
76 ms |
10828 KB |
sub1_15.txt |
AC |
25 ms |
4944 KB |
sub1_16.txt |
AC |
17 ms |
3888 KB |
sub1_17.txt |
AC |
3 ms |
3512 KB |
sub1_18.txt |
AC |
2 ms |
3508 KB |
sub1_19.txt |
AC |
2 ms |
3444 KB |
sub1_20.txt |
AC |
267 ms |
31624 KB |
sub1_21.txt |
AC |
200 ms |
24684 KB |
sub1_22.txt |
AC |
296 ms |
35236 KB |
sub1_23.txt |
AC |
157 ms |
20004 KB |
sub1_24.txt |
AC |
322 ms |
37092 KB |
sub1_25.txt |
AC |
223 ms |
27056 KB |
sub1_26.txt |
AC |
131 ms |
17380 KB |
sub1_27.txt |
AC |
268 ms |
31868 KB |
sub1_28.txt |
AC |
90 ms |
12072 KB |