Problem p02753 (C++)

Buggy submission (status: Runtime Error):
// R<3S
#include <bits/stdc++.h>
#define FAST                                                                   \
  std::ios_base::sync_with_stdio(false);                                       \
  cin.tie(0);                                                                  \
  cout.tie(0);
#define DECIMAL(n)                                                             \
  std::cout << std::fixed;                                                     \
  std::cout << std::setprecision(n);
#define hell 1000000007
#define PI 3.14159265358979323844
#define mp make_pair
#define pb push_back
#define fi first
#define se second
#define ALL(v) v.begin(), v.end()
#define SORT(v) sort(ALL(v))
#define REVERSE(v) reverse(ALL(v))
#define endl "\n"
#define maxc(v) max_element(all(v))
#define minc(v) min_element(all(v))
#define GCD(m, n) __gcd(m, n)
#define LCM(m, n) m *(n / GCD(m, n))
#define inputarr(a, n)                                                         \
  for (int i = 0; i < n; ++i)                                                  \
  cin >> a[i]
#define initarr(a, n, x)                                                       \
  for (int i = 0; i < n; ++i)                                                  \
  a[i] = x
#define rep(i, n) for (int i = 0; i < (n); ++i)
#define repA(i, a, n) for (int i = a; i <= (n); ++i)
#define repD(i, a, n) for (int i = a; i >= (n); --i)
#define trav(a, x) for (auto &a : x)
#define sz(a) (int)a.size()
#define sl(a) (int)a.length()
#define invect(data, n, commands)                                              \
  for (int i = 0; i < n; i++) {                                                \
    int tmp;                                                                   \
    cin >> tmp;                                                                \
    data.pb(tmp);                                                              \
    commands                                                                   \
  }
#define inset(data, n, commands)                                               \
  for (int i = 0; i < n; i++) {                                                \
    int tmp;                                                                   \
    cin >> tmp;                                                                \
    data.insert(tmp);                                                          \
    commands                                                                   \
  }
#define ll long long
#define ld long double
#define pii std::pair<int, int>
#define pll std::pair<ll, ll>
#define vi vector<int>
#define vvi vector<vi>
#define vii vector<pii>
#define mii map<int, int>
#define trace1(x) cerr << #x << ": " << x << endl
#define trace2(x, y) cerr << #x << ": " << x << " | " << #y << ": " << y << endl
#define trace3(x, y, z)                                                        \
  cerr << #x << ":" << x << " | " << #y << ": " << y << " | " << #z << ": "    \
       << z << endl
#define trace4(a, b, c, d)                                                     \
  cerr << #a << ": " << a << " | " << #b << ": " << b << " | " << #c << ": "   \
       << c << " | " << #d << ": " << d << endl
#define trace5(a, b, c, d, e)                                                  \
  cerr << #a << ": " << a << " | " << #b << ": " << b << " | " << #c << ": "   \
       << c << " | " << #d << ": " << d << " | " << #e << ": " << e << endl
#define trace6(a, b, c, d, e, f)                                               \
  cerr << #a << ": " << a << " | " << #b << ": " << b << " | " << #c << ": "   \
       << c << " | " << #d << ": " << d << " | " << #e << ": " << e << " | "   \
       << #f << ": " << f << endl

using namespace std;

void solve() {

  string s;
  cin >> s;
  int len = sz(s);
  rep(i, len - 1) {
    if ((s[i + 1] == 'A' && s[i] == 'B') || (s[i + 1] == 'B' && s[i] == 'A')) {
      cout << "Yes";
      return;
    }
  }
  cout << "No";
}

int main() {
  FAST
#ifndef ONLINE_JUDGE
      freopen("input.txt", "r", stdin);
  freopen("output.txt", "w", stdout);
#endif
  int t;
  t = 1;
  // cin>>t;
  while (t--) {
    solve();
  }

  return 0;
}


Fixed submission:
// R<3S
#include <bits/stdc++.h>
#define FAST                                                                   \
  std::ios_base::sync_with_stdio(false);                                       \
  cin.tie(0);                                                                  \
  cout.tie(0);
#define DECIMAL(n)                                                             \
  std::cout << std::fixed;                                                     \
  std::cout << std::setprecision(n);
#define hell 1000000007
#define PI 3.14159265358979323844
#define mp make_pair
#define pb push_back
#define fi first
#define se second
#define ALL(v) v.begin(), v.end()
#define SORT(v) sort(ALL(v))
#define REVERSE(v) reverse(ALL(v))
#define endl "\n"
#define maxc(v) max_element(all(v))
#define minc(v) min_element(all(v))
#define GCD(m, n) __gcd(m, n)
#define LCM(m, n) m *(n / GCD(m, n))
#define inputarr(a, n)                                                         \
  for (int i = 0; i < n; ++i)                                                  \
  cin >> a[i]
#define initarr(a, n, x)                                                       \
  for (int i = 0; i < n; ++i)                                                  \
  a[i] = x
#define rep(i, n) for (int i = 0; i < (n); ++i)
#define repA(i, a, n) for (int i = a; i <= (n); ++i)
#define repD(i, a, n) for (int i = a; i >= (n); --i)
#define trav(a, x) for (auto &a : x)
#define sz(a) (int)a.size()
#define sl(a) (int)a.length()
#define invect(data, n, commands)                                              \
  for (int i = 0; i < n; i++) {                                                \
    int tmp;                                                                   \
    cin >> tmp;                                                                \
    data.pb(tmp);                                                              \
    commands                                                                   \
  }
#define inset(data, n, commands)                                               \
  for (int i = 0; i < n; i++) {                                                \
    int tmp;                                                                   \
    cin >> tmp;                                                                \
    data.insert(tmp);                                                          \
    commands                                                                   \
  }
#define ll long long
#define ld long double
#define pii std::pair<int, int>
#define pll std::pair<ll, ll>
#define vi vector<int>
#define vvi vector<vi>
#define vii vector<pii>
#define mii map<int, int>
#define trace1(x) cerr << #x << ": " << x << endl
#define trace2(x, y) cerr << #x << ": " << x << " | " << #y << ": " << y << endl
#define trace3(x, y, z)                                                        \
  cerr << #x << ":" << x << " | " << #y << ": " << y << " | " << #z << ": "    \
       << z << endl
#define trace4(a, b, c, d)                                                     \
  cerr << #a << ": " << a << " | " << #b << ": " << b << " | " << #c << ": "   \
       << c << " | " << #d << ": " << d << endl
#define trace5(a, b, c, d, e)                                                  \
  cerr << #a << ": " << a << " | " << #b << ": " << b << " | " << #c << ": "   \
       << c << " | " << #d << ": " << d << " | " << #e << ": " << e << endl
#define trace6(a, b, c, d, e, f)                                               \
  cerr << #a << ": " << a << " | " << #b << ": " << b << " | " << #c << ": "   \
       << c << " | " << #d << ": " << d << " | " << #e << ": " << e << " | "   \
       << #f << ": " << f << endl

using namespace std;

void solve() {

  string s;
  cin >> s;
  int len = sz(s);
  rep(i, len - 1) {
    if ((s[i + 1] == 'A' && s[i] == 'B') || (s[i + 1] == 'B' && s[i] == 'A')) {
      cout << "Yes";
      return;
    }
  }
  cout << "No";
}

int main() {
  FAST

      int t;
  t = 1;
  // cin>>t;
  while (t--) {
    solve();
  }

  return 0;
}