Problem p02958 (C++)

Buggy submission (status: Runtime Error):
#include <bits/stdc++.h>
#define SORT(a) sort(a.begin(), a.end())
#define RSORT(a) sort(a.rbegin(), a.rend())
#define REP(i, n) for (int i = 0; i < n; i++)
#define FOR(i, start, end) for (int i = start; i < end; i++)
#define ALL(a) a.begin(), a.end()
#define MOD(a) a %= 1'000'000'007
using ll = long long;
using namespace std;
const int INF32 = 1'050'000'000;
const long long INF64 = 4'000'000'000'000'000'000;
const int MOD7 = 1'000'000'007;
const int MOD9 = 1'000'000'009;
template <class T> inline bool chmin(T &a, T b) {
  if (a > b) {
    a = b;
    return true;
  }
  return false;
}
template <class T> inline bool chmax(T &a, T b) {
  if (a < b) {
    a = b;
    return true;
  }
  return false;
}
void print() { std::cout << '\n'; }
template <class H, class... T> void print(H &&head, T &&...args) {
  std::cout << head;
  sizeof...(args) == 0 ? std::cout << "" : std::cout << ' ';
  print(std::forward<T>(args)...);
}
template <class T> void print(std::vector<T> &v) {
  for (int i = 0; i < v.size(); i++) {
    std::cout << v[i];
    i == v.size() - 1 ? std::cout << '\n' : std::cout << ' ';
  }
}
template <class T> void print(std::vector<std::vector<T>> &v) {
  for (int i = 0; i < v.size(); i++) {
    for (int j = 0; j < v[i].size(); j++) {
      std::cout << v[i][j];
      j == v[i].size() - 1 ? std::cout << '\n' : std::cout << ' ';
    }
  }
}

int main() {
  cin.tie(0);
  ios::sync_with_stdio(false);

  int N;
  cin >> N;
  vector<int> a(N);
  for (auto &&i : a) {
    cin >> i;
  }

  int cnt = -1;
  int cnt2 = -1;
  FOR(i, 1, N) {
    if (0 <= cnt && a[i - 1] > a[i]) {
      cnt2 = i;
      break;
    }
    if (cnt == -1 && a[i - 1] > a[i]) {
      cnt = i - 1;
    }
  }
  swap(a[cnt], a[cnt2]);
  FOR(i, 1, N) {
    if (a[i] < a[i - 1]) {
      print("NO");
      return 0;
    }
  }
  print("YES");

  return 0;
}

Fixed submission:
#include <bits/stdc++.h>
#define SORT(a) sort(a.begin(), a.end())
#define RSORT(a) sort(a.rbegin(), a.rend())
#define REP(i, n) for (int i = 0; i < n; i++)
#define FOR(i, start, end) for (int i = start; i < end; i++)
#define ALL(a) a.begin(), a.end()
#define MOD(a) a %= 1'000'000'007
using ll = long long;
using namespace std;
const int INF32 = 1'050'000'000;
const long long INF64 = 4'000'000'000'000'000'000;
const int MOD7 = 1'000'000'007;
const int MOD9 = 1'000'000'009;
template <class T> inline bool chmin(T &a, T b) {
  if (a > b) {
    a = b;
    return true;
  }
  return false;
}
template <class T> inline bool chmax(T &a, T b) {
  if (a < b) {
    a = b;
    return true;
  }
  return false;
}
void print() { std::cout << '\n'; }
template <class H, class... T> void print(H &&head, T &&...args) {
  std::cout << head;
  sizeof...(args) == 0 ? std::cout << "" : std::cout << ' ';
  print(std::forward<T>(args)...);
}
template <class T> void print(std::vector<T> &v) {
  for (int i = 0; i < v.size(); i++) {
    std::cout << v[i];
    i == v.size() - 1 ? std::cout << '\n' : std::cout << ' ';
  }
}
template <class T> void print(std::vector<std::vector<T>> &v) {
  for (int i = 0; i < v.size(); i++) {
    for (int j = 0; j < v[i].size(); j++) {
      std::cout << v[i][j];
      j == v[i].size() - 1 ? std::cout << '\n' : std::cout << ' ';
    }
  }
}

int main() {
  cin.tie(0);
  ios::sync_with_stdio(false);

  int N;
  cin >> N;
  vector<int> a(N);
  for (auto &&i : a) {
    cin >> i;
  }

  int cnt = -1;
  int cnt2 = -1;
  FOR(i, 1, N) {
    if (0 <= cnt && a[i - 1] > a[i]) {
      cnt2 = i;
      break;
    }
    if (cnt == -1 && a[i - 1] > a[i]) {
      cnt = i - 1;
    }
  }
  if (0 <= cnt && 0 <= cnt2)
    swap(a[cnt], a[cnt2]);
  FOR(i, 1, N) {
    if (a[i] < a[i - 1]) {
      print("NO");
      return 0;
    }
  }
  print("YES");

  return 0;
}