FashionInBerland.java

/*  https://codeforces.com/contest/691/problem/A
#implementation
    count the number of 0 in the array.
    special case: when only have an array with length 1.
*/
import java.util.Scanner;

public class FashionInBerland {

  static String myFunction() {
    Scanner obj = new Scanner(System.in);
    int number = obj.nextInt();

    // special case
    if (number == 1) {
      if (0 == obj.nextInt()) {
        return "NO";
      } else {
        return "YES";
      }
    }

    int countZero = 0;
    for (int i = 0; i < number; i++) {
      if (0 == obj.nextInt()) {
        countZero++;
      }
      if (countZero > 1) {
        break;
      }
    }

    if (countZero != 1) {
      return "NO";
    }

    return "YES";
  }

  public static void main(String argr[]) {
    System.out.println(myFunction());
  }
}