Problem p02554 (C++) — buggy submission, verdict: Runtime Error

/*
このコード、と～おれ!
Be accepted!
∧＿∧　
（｡･ω･｡)つ━☆・*。
⊂　　 ノ 　　　・゜+.
　しーＪ　　　°。+ *´¨)
 　　　　　　　　　.· ´¸.·*´¨) ¸.·*¨)
                  　　　　　　　　　　(¸.·´ (¸.·'* ☆
*/

#include <algorithm>
#include <bitset>
#include <cassert>
#include <cmath>
#include <complex>
#include <cstdio>
#include <cstring>
#include <functional>
#include <iomanip>
#include <iostream>
#include <list>
#include <map>
#include <numeric>
#include <queue>
#include <random>
#include <regex>
#include <set>
#include <stack>
#include <string>
#include <unordered_map>
#include <vector>

////多倍長整数, cpp_intで宣言
// #include <boost/multiprecision/cpp_int.hpp>
// using namespace boost::multiprecision;

#pragma GCC target("avx2")
#pragma GCC optimization("Ofast")
#pragma GCC optimization("unroll-loops")
#pragma GCC target("sse,sse2,sse3,ssse3,sse4,popcnt,abm,mmx,avx,tune=native")
#define repeat(i, n, m) for (int i = n; i < (m); ++i)
#define rep(i, n) for (int i = 0; i < (n); ++i)
#define printynl(a) printf(a ? "yes\\n" : "no\\n")
#define printyn(a) printf(a ? "Yes\\n" : "No\\n")
#define printYN(a) printf(a ? "YES\\n" : "NO\\n")
#define printim(a) printf(a ? "possible\\n" : "imposible\\n")
#define printdb(a) printf("%.50lf\\n", a)    // 少数出力
#define printLdb(a) printf("%.50Lf\\n", a)   // 少数出力
#define printdbd(a) printf("%.16lf\\n", a)   // 少数出力(桁少なめ)
#define prints(s) printf("%s\\n", s.c_str()) // string出力
#define all(x) (x).begin(), (x).end()
#define deg_to_rad(deg) (((deg) / 360.0L) * 2.0L * PI)
#define rad_to_deg(rad) (((rad) / 2.0L / PI) * 360.0L)
#define Please return
#define AC 0
#define manhattan_dist(a, b, c, d)                                             \\
  (abs(a - c) + abs(b - d)) /*(a, b) から (c, d) のマンハッタン距離 */
#define inf numeric_limits<double>::infinity();
#define linf numeric_limits<long double>::infinity()

using ll = long long;
using ull = unsigned long long;

constexpr int INF = 1073741823;
constexpr int MINF = -1073741823;
constexpr ll LINF = ll(4661686018427387903);
constexpr ll MOD = 1e9 + 7;
constexpr ll mod = 998244353;
constexpr long double eps = 1e-6;
const long double PI = acosl(-1.0L);

using namespace std;

void scans(string &str) {
  char c;
  str = "";
  scanf("%c", &c);
  if (c == '\\n')
    scanf("%c", &c);
  while (c != '\\n' && c != -1 && c != ' ') {
    str += c;
    scanf("%c", &c);
  }
}

void scanc(char &str) {
  char c;
  scanf("%c", &c);
  if (c == -1)
    return;
  while (c == '\\n') {
    scanf("%c", &c);
  }
  str = c;
}

double acot(double x) { return PI / 2 - atan(x); }

ll LSB(ll n) { return (n & (-n)); }

template <typename T> inline T chmin(T &a, const T &b) {
  if (a > b)
    a = b;
  return a;
}

template <typename T> inline T chmax(T &a, const T &b) {
  if (a < b)
    a = b;
  return a;
}

/*-----------------------------------------ここからコード-----------------------------------------*/

/*
 * @title modint
 * @docs kyopro/docs/modint.md
 */

template <int mod> struct modint {
  int val;

  modint() : val(0){};
  modint(ll x) : val(x >= 0 ? x % mod : (mod + x % mod) % mod){};

  modint &operator=(const modint &x) {
    val = x.val;
    return *this;
  }

  modint &operator+=(const modint &x) {
    val += x.val;
    if (val >= mod)
      val -= mod;
    return *this;
  }

  modint &operator-=(const modint &x) {
    val += mod - x.val;
    if (val >= mod)
      val -= mod;
    return *this;
  }

  modint &operator*=(const modint &x) {
    val = (int)((ll)val * (ll)x.val % mod);
    return *this;
  }

  modint &operator/=(const modint &x) {
    int a = x.val, b = mod, u = 1, v = 0, t;
    while (b > 0) {
      t = a / b;
      swap(a -= t * b, b);
      swap(u -= t * v, v);
    }
    *this *= modint(u);
    return *this;
  }

  modint operator++() {
    val = (val + 1 == mod ? 0 : val + 1);
    return *this;
  }

  modint operator--() {
    val = (val == 0 ? mod - 1 : val - 1);
    return *this;
  }

  modint operator+(const modint &x) const { return (modint(*this) += x); }

  modint operator-(const modint &x) const { return (modint(*this) -= x); }

  modint operator*(const modint &x) const { return (modint(*this) *= x); }

  modint operator/(const modint &x) const { return (modint(*this) /= x); }

  bool operator==(const modint &x) const { return (val == x.val); }

  bool operator!=(const modint &x) const { return (val != x.val); }

  bool operator<(const modint &x) const { return (val < x.val); }

  bool operator>(const modint &x) const { return (val > x.val); }

  modint pow(ll n) {
    modint ret(1), a(val);
    while (n > 0) {
      if (n % 2)
        ret *= a;
      a *= a;
      n /= 2;
    }
    return ret;
  }

  static int getmod() { return mod; };
};

using ModInt = modint<MOD>;
using Modint = modint<mod>;

int main() {

  int n;
  scanf("%d", &n);
  ModInt ans, p = 10, q = 9, r = 8;
  ans = p.pow(n) - q.pow(n) * 2 + r.pow(n);
  printf("%d\\n", ans.val);

  Please AC;
}


Error: 0

Fixed submission:

/*
このコード、と～おれ!
Be accepted!
∧＿∧　
（｡･ω･｡)つ━☆・*。
⊂　　 ノ 　　　・゜+.
　しーＪ　　　°。+ *´¨)
 　　　　　　　　　.· ´¸.·*´¨) ¸.·*¨)
                  　　　　　　　　　　(¸.·´ (¸.·'* ☆
*/

#include <algorithm>
#include <bitset>
#include <cassert>
#include <cmath>
#include <complex>
#include <cstdio>
#include <cstring>
#include <functional>
#include <iomanip>
#include <iostream>
#include <list>
#include <map>
#include <numeric>
#include <queue>
#include <random>
#include <regex>
#include <set>
#include <stack>
#include <string>
#include <unordered_map>
#include <vector>

////多倍長整数, cpp_intで宣言
// #include <boost/multiprecision/cpp_int.hpp>
// using namespace boost::multiprecision;

#pragma GCC target("avx2")
#pragma GCC optimization("Ofast")
#pragma GCC optimization("unroll-loops")
#pragma GCC target("sse,sse2,sse3,ssse3,sse4,popcnt,abm,mmx,avx,tune=native")
#define repeat(i, n, m) for (int i = n; i < (m); ++i)
#define rep(i, n) for (int i = 0; i < (n); ++i)
#define printynl(a) printf(a ? "yes\\n" : "no\\n")
#define printyn(a) printf(a ? "Yes\\n" : "No\\n")
#define printYN(a) printf(a ? "YES\\n" : "NO\\n")
#define printim(a) printf(a ? "possible\\n" : "imposible\\n")
#define printdb(a) printf("%.50lf\\n", a)    // 少数出力
#define printLdb(a) printf("%.50Lf\\n", a)   // 少数出力
#define printdbd(a) printf("%.16lf\\n", a)   // 少数出力(桁少なめ)
#define prints(s) printf("%s\\n", s.c_str()) // string出力
#define all(x) (x).begin(), (x).end()
#define deg_to_rad(deg) (((deg) / 360.0L) * 2.0L * PI)
#define rad_to_deg(rad) (((rad) / 2.0L / PI) * 360.0L)
#define Please return
#define AC 0
#define manhattan_dist(a, b, c, d)                                             \\
  (abs(a - c) + abs(b - d)) /*(a, b) から (c, d) のマンハッタン距離 */
#define inf numeric_limits<double>::infinity();
#define linf numeric_limits<long double>::infinity()

using ll = long long;
using ull = unsigned long long;

constexpr int INF = 1073741823;
constexpr int MINF = -1073741823;
constexpr ll LINF = ll(4661686018427387903);
constexpr ll MOD = 1e9 + 7;
constexpr ll mod = 998244353;
constexpr long double eps = 1e-6;
const long double PI = acosl(-1.0L);

using namespace std;

void scans(string &str) {
  char c;
  str = "";
  scanf("%c", &c);
  if (c == '\\n')
    scanf("%c", &c);
  while (c != '\\n' && c != -1 && c != ' ') {
    str += c;
    scanf("%c", &c);
  }
}

void scanc(char &str) {
  char c;
  scanf("%c", &c);
  if (c == -1)
    return;
  while (c == '\\n') {
    scanf("%c", &c);
  }
  str = c;
}

double acot(double x) { return PI / 2 - atan(x); }

ll LSB(ll n) { return (n & (-n)); }

template <typename T> inline T chmin(T &a, const T &b) {
  if (a > b)
    a = b;
  return a;
}

template <typename T> inline T chmax(T &a, const T &b) {
  if (a < b)
    a = b;
  return a;
}

/*-----------------------------------------ここからコード-----------------------------------------*/

/*
 * @title modint
 * @docs kyopro/docs/modint.md
 */

template <int mod> struct modint {
  int val;

  modint() : val(0){};
  modint(ll x) : val(x >= 0 ? x % mod : (mod + x % mod) % mod){};

  modint &operator=(const modint &x) {
    val = x.val;
    return *this;
  }

  modint &operator+=(const modint &x) {
    val += x.val;
    if (val >= mod)
      val -= mod;
    return *this;
  }

  modint &operator-=(const modint &x) {
    val += mod - x.val;
    if (val >= mod)
      val -= mod;
    return *this;
  }

  modint &operator*=(const modint &x) {
    val = (int)((ll)val * (ll)x.val % mod);
    return *this;
  }

  modint &operator/=(const modint &x) {
    int a = x.val, b = mod, u = 1, v = 0, t;
    while (b > 0) {
      t = a / b;
      swap(a -= t * b, b);
      swap(u -= t * v, v);
    }
    *this *= modint(u);
    return *this;
  }

  modint operator++() {
    val = (val + 1 == mod ? 0 : val + 1);
    return *this;
  }

  modint operator--() {
    val = (val == 0 ? mod - 1 : val - 1);
    return *this;
  }

  modint operator+(const modint &x) const { return (modint(*this) += x); }

  modint operator-(const modint &x) const { return (modint(*this) -= x); }

  modint operator*(const modint &x) const { return (modint(*this) *= x); }

  modint operator/(const modint &x) const { return (modint(*this) /= x); }

  bool operator==(const modint &x) const { return (val == x.val); }

  bool operator!=(const modint &x) const { return (val != x.val); }

  bool operator<(const modint &x) const { return (val < x.val); }

  bool operator>(const modint &x) const { return (val > x.val); }

  modint pow(ll n) {
    modint ret(1), a(val);
    while (n > 0) {
      if (n % 2)
        ret *= a;
      a *= a;
      n /= 2;
    }
    return ret;
  }

  static int getmod() { return mod; };
};

using ModInt = modint<MOD>;
using Modint = modint<mod>;

const int MAX = 510000;

long long fac[MAX], finv[MAX], inv[MAX];

// テーブルを作る前処理
void COMinit() {
  fac[0] = fac[1] = 1;
  finv[0] = finv[1] = 1;
  inv[1] = 1;
  for (int i = 2; i < MAX; i++) {
    fac[i] = fac[i - 1] * i % MOD;
    inv[i] = MOD - inv[MOD % i] * (MOD / i) % MOD;
    finv[i] = finv[i - 1] * inv[i] % MOD;
  }
}

// 二項係数計算
long long COM(int n, int k) {
  if (n < k)
    return 0;
  if (n < 0 || k < 0)
    return 0;
  return fac[n] * (finv[k] * finv[n - k] % MOD) % MOD;
}

int main() {

  int n;
  scanf("%d", &n);
  ModInt ans = 0, p = 8, q = 2;
  COMinit();
  for (int i = 2; i <= n; ++i) {
    ans += q.pow(i - 2) * COM(n, i) * p.pow(n - i) * 2;
  }

  printf("%d\\n", ans.val);

  Please AC;
}