Problem p02711 (C++)

Buggy submission (status: Time Limit Exceeded):
#include <bits/stdc++.h>
using namespace std;

#define LL long long
typedef pair<int, int> pii;

template <typename T> inline void read(T &x) {
  static char _c;
  static bool _f;

  x = 0;
  _f = 0;
  _c = getchar();

  while (_c < '0' || '9' < _c) {
    if (_c == '-')
      _f = true;
    _c = getchar();
  }
  while ('0' <= _c && _c <= '9') {
    x = (x << 1) + (x << 3) + (_c & 15);
    _c = getchar();
  }
  if (_f)
    x = -x;
}

template <typename T> inline void Min(T &x, T y) {
  if (y < x)
    x = y;
}
template <typename T> inline void Max(T &x, T y) {
  if (x < y)
    x = y;
}

#define lowbit(x) ((x) & -(x))
#define lson l, mid, id << 1
#define rson mid + 1, r, id << 1 | 1
#define ls id << 1
#define rs id << 1 | 1
#define MID(l, r) ((l) + (((r) - (l)) >> 1))
#define fi first
#define se second
#define mk make_pair
#define pb push_back

const int INF = 0x3f3f3f3f;
const double pi = (double)acos(-1.0);
const double eps = (double)1e-8;
// const int MOD = (int) 1e9 + 7;
// const int MOD = (int) 998244353;
int MOD = 998244353;
const int e5 = (int)1e5 + 5;
const int maxn = (int)1e5 + 20;
const int maxm = (int)1e6 + 20;

inline int sig(double x) { return x < -eps ? -1 : eps < x; }
LL fp(LL a, LL n, LL mod = MOD) {
  if (n < 0)
    a = fp(a, mod - 2, mod), n = -n;
  LL res = 1;
  for (; n; n >>= 1, a = a * a % mod)
    if (n & 1)
      res = res * a % mod;
  return res;
}

struct Mint {
  LL x;
  Mint() { x = 0; }
  Mint(int _x) : x(_x) {}
  Mint(LL _x) : x(_x) {}
  Mint operator-() const { return Mint(MOD - x); }
  Mint operator+(const Mint &rhs) const {
    LL res = x + rhs.x;
    if (res >= MOD)
      res -= MOD;
    return Mint(res);
  }
  Mint operator-(const Mint &rhs) const {
    LL res = x - rhs.x;
    if (res < 0)
      res += MOD;
    return Mint(res);
  }
  Mint operator*(const Mint &rhs) const { return Mint(x * rhs.x % MOD); }
  Mint operator/(const Mint &rhs) const {
    return Mint(x * fp(rhs.x, -1) % MOD);
  }
  Mint &operator+=(const Mint &rhs) {
    x += rhs.x;
    if (x >= MOD)
      x -= MOD;
    return *this;
  }
  Mint &operator*=(const Mint &rhs) {
    x = (x * rhs.x) % MOD;
    return *this;
  }
  bool operator==(const Mint &rhs) const { return x == rhs.x; }
  bool operator!=(const Mint &rhs) const { return x != rhs.x; }
  friend ostream &operator<<(ostream &out, const Mint &rhs) {
    return out << rhs.x;
  }
  friend istream &operator>>(istream &in, Mint &rhs) { return in >> rhs.x; }
};

void work() {
  int x;
  read(x);

  while (x) {
    if (x % 10 == 7) {
      cout << "Yes";
      return;
    }
    x /= 10;
  }
  cout << "No";
}

int main(int argc, char **argv) {
#ifdef yukihana0416
  freopen("in.txt", "r", stdin);
// freopen("out.txt", "w", stdout);
#endif // yukihana0416
       //    get_prime();
       //    pre();
  int tc = 1;
  read(tc);
  for (int ca = 1; ca <= tc; ca++) {
    //        printf("Case #%d: ", ca);
    work();
  }
  return 0;
}


Fixed submission:
#include <bits/stdc++.h>
using namespace std;

#define LL long long
typedef pair<int, int> pii;

template <typename T> inline void read(T &x) {
  static char _c;
  static bool _f;

  x = 0;
  _f = 0;
  _c = getchar();

  while (_c < '0' || '9' < _c) {
    if (_c == '-')
      _f = true;
    _c = getchar();
  }
  while ('0' <= _c && _c <= '9') {
    x = (x << 1) + (x << 3) + (_c & 15);
    _c = getchar();
  }
  if (_f)
    x = -x;
}

template <typename T> inline void Min(T &x, T y) {
  if (y < x)
    x = y;
}
template <typename T> inline void Max(T &x, T y) {
  if (x < y)
    x = y;
}

#define lowbit(x) ((x) & -(x))
#define lson l, mid, id << 1
#define rson mid + 1, r, id << 1 | 1
#define ls id << 1
#define rs id << 1 | 1
#define MID(l, r) ((l) + (((r) - (l)) >> 1))
#define fi first
#define se second
#define mk make_pair
#define pb push_back

const int INF = 0x3f3f3f3f;
const double pi = (double)acos(-1.0);
const double eps = (double)1e-8;
// const int MOD = (int) 1e9 + 7;
// const int MOD = (int) 998244353;
int MOD = 998244353;
const int e5 = (int)1e5 + 5;
const int maxn = (int)1e5 + 20;
const int maxm = (int)1e6 + 20;

inline int sig(double x) { return x < -eps ? -1 : eps < x; }
LL fp(LL a, LL n, LL mod = MOD) {
  if (n < 0)
    a = fp(a, mod - 2, mod), n = -n;
  LL res = 1;
  for (; n; n >>= 1, a = a * a % mod)
    if (n & 1)
      res = res * a % mod;
  return res;
}

struct Mint {
  LL x;
  Mint() { x = 0; }
  Mint(int _x) : x(_x) {}
  Mint(LL _x) : x(_x) {}
  Mint operator-() const { return Mint(MOD - x); }
  Mint operator+(const Mint &rhs) const {
    LL res = x + rhs.x;
    if (res >= MOD)
      res -= MOD;
    return Mint(res);
  }
  Mint operator-(const Mint &rhs) const {
    LL res = x - rhs.x;
    if (res < 0)
      res += MOD;
    return Mint(res);
  }
  Mint operator*(const Mint &rhs) const { return Mint(x * rhs.x % MOD); }
  Mint operator/(const Mint &rhs) const {
    return Mint(x * fp(rhs.x, -1) % MOD);
  }
  Mint &operator+=(const Mint &rhs) {
    x += rhs.x;
    if (x >= MOD)
      x -= MOD;
    return *this;
  }
  Mint &operator*=(const Mint &rhs) {
    x = (x * rhs.x) % MOD;
    return *this;
  }
  bool operator==(const Mint &rhs) const { return x == rhs.x; }
  bool operator!=(const Mint &rhs) const { return x != rhs.x; }
  friend ostream &operator<<(ostream &out, const Mint &rhs) {
    return out << rhs.x;
  }
  friend istream &operator>>(istream &in, Mint &rhs) { return in >> rhs.x; }
};

void work() {
  int x;
  read(x);

  while (x) {
    if (x % 10 == 7) {
      cout << "Yes";
      return;
    }
    x /= 10;
  }
  cout << "No";
}

int main(int argc, char **argv) {
#ifdef yukihana0416
  freopen("in.txt", "r", stdin);
// freopen("out.txt", "w", stdout);
#endif // yukihana0416
       //    get_prime();
       //    pre();
  int tc = 1;
  //    read(tc);
  for (int ca = 1; ca <= tc; ca++) {
    //        printf("Case #%d: ", ca);
    work();
  }
  return 0;
}