Problem p02574 (C++) — buggy submission, verdict: Time Limit Exceeded

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

#define PI 3.141592653589
#define ll long long int
#define ld long double
#define vi vector<int>
#define vl vector<ll>
#define ii pair<int, int>
#define pb push_back
#define mp make_pair
#define ff first
#define ss second
#define pll pair<ll, ll>
#define vv vector
int MOD = 1e9 + 7;
ll power(ll a, ll b) { // a^b
  ll res = 1;
  a = a % MOD;
  while (b > 0) {
    if (b & 1) {
      res = (res * a) % MOD;
      b--;
    }
    a = (a * a) % MOD;
    b >>= 1;
  }
  return res;
}
ll fermat_inv(ll y) { return power(y, MOD - 2); }
ll gcd(ll a, ll b) { return (b == 0) ? a : gcd(b, a % b); }
ll min(ll a, ll b) { return (a > b) ? b : a; }
ll max(ll a, ll b) { return (a > b) ? a : b; }
bool prime[1000005];
int freq[1000005] = {0};
int a[1000005] = {0};
vi primes;
void SieveOfEratosthenes(int n) {
  memset(prime, true, sizeof(prime));
  for (int p = 2; p <= n; p++) {
    if (prime[p] == true) {
      primes.pb(p);
      for (int i = p; i <= n; i += p)
        prime[i] = false, freq[p] += a[i];
    }
  }
}

int main() {
  ios_base::sync_with_stdio(false);
  cin.tie(NULL);
#ifndef ONLINE_JUDGE
  freopen("input.txt", "r", stdin);
  freopen("output.txt", "w", stdout);
#endif

  int t = 1;
  // cin>>t;

  // factorial(100005);
  while (t--) {
    int n;
    cin >> n;
    for (int i = 0; i < n; i++) {
      int x;
      cin >> x;
      a[x]++;
    }
    SieveOfEratosthenes(1000000);

    bool cp = true, cs = true;
    for (int i : primes) {
      if (freq[i] > 1)
        cp = false;
      if (freq[i] >= n)
        cs = false;
    }
    if (cp)
      cout << "pairwise coprime";
    else if (cs)
      cout << "setwise coprime";
    else
      cout << "not coprime";
  }
}

Error: TLE

Fixed submission:

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

#define PI 3.141592653589
#define ll long long int
#define ld long double
#define vi vector<int>
#define vl vector<ll>
#define ii pair<int, int>
#define pb push_back
#define mp make_pair
#define ff first
#define ss second
#define pll pair<ll, ll>
#define vv vector
int MOD = 1e9 + 7;
ll power(ll a, ll b) { // a^b
  ll res = 1;
  a = a % MOD;
  while (b > 0) {
    if (b & 1) {
      res = (res * a) % MOD;
      b--;
    }
    a = (a * a) % MOD;
    b >>= 1;
  }
  return res;
}
ll fermat_inv(ll y) { return power(y, MOD - 2); }
ll gcd(ll a, ll b) { return (b == 0) ? a : gcd(b, a % b); }
ll min(ll a, ll b) { return (a > b) ? b : a; }
ll max(ll a, ll b) { return (a > b) ? a : b; }
bool prime[1000001];
vi primes;
void SieveOfEratosthenes(int n) {
  memset(prime, true, sizeof(prime));
  for (int p = 2; p * p <= n; p++) {
    if (prime[p] == true) {
      for (int i = p * p; i <= n; i += p)
        prime[i] = false;
    }
  }
  for (int p = 2; p < 1000001; p++)
    if (prime[p])
      primes.pb(p);
}

int freq[1000005];
int a[1000005];
int main() {
  ios_base::sync_with_stdio(false);
  cin.tie(NULL);
#ifndef ONLINE_JUDGE
  freopen("input.txt", "r", stdin);
  freopen("output.txt", "w", stdout);
#endif

  int t = 1;
  // cin>>t;
  SieveOfEratosthenes(1000000);
  // factorial(100005);
  while (t--) {
    int n;
    cin >> n;
    for (int i = 0; i < n; i++)
      cin >> a[i];
    for (int i = 0; i < n; i++) {
      int temp = a[i];
      for (int j : primes) {
        if (j > temp)
          break;
        if (temp % j == 0) {
          freq[j]++;
          while (temp % j == 0)
            temp /= j;
        }
      }
    }
    bool cp = true, cs = true;
    for (int i : primes) {
      if (freq[i] > 1)
        cp = false;
      if (freq[i] == n)
        cs = false;
    }
    if (cp)
      cout << "pairwise coprime";
    else if (cs)
      cout << "setwise coprime";
    else
      cout << "not coprime";
  }
}