Laivanupotus

#include <iostream>
using namespace std;
int n;

int main(){
  ios_base::sync_with_stdio(0); cin.tie(0);
  
  cin >> n;
  for (int i=0; i<n; ++i){
    for (int j=0; j<n; ++j){
      if (n<=3) cout << ".";
      else if ((j+i)%4==3) cout << "*";
      else cout << ".";
    }cout << "\n";
  }
}

Test 1

Group: 1

Verdict: ACCEPTED

Test 2

Group: 1

Verdict: ACCEPTED

Test 3

Group: 1

Verdict: ACCEPTED

Test 4

Group: 1

Verdict: ACCEPTED

Test 5

Group: 1

Verdict: ACCEPTED

Test 6

Group: 2

Verdict: ACCEPTED

Test 7

Group: 2

Verdict: ACCEPTED

Test 8

Group: 2

Verdict: ACCEPTED

Test 9

Group: 2

Verdict: ACCEPTED

Test 10

Group: 2

Verdict: ACCEPTED

Test 11

Group: 3

Verdict: ACCEPTED

Test 12

Group: 3

Verdict: ACCEPTED

Test 13

Group: 3

Verdict: ACCEPTED

Test 14

Group: 3

Verdict: ACCEPTED

Test 15

Group: 3

Verdict: ACCEPTED