// Write a program that takes an integer command-line argument n,
// reads in n-1 distinct integers between 1 and n, and determines the missing value.

import java.util.Arrays;

public class Tester {
    public static void main(String[] args) {
        int n = Integer.parseInt(args[0]);
        StdOut.println("Please enter " + (n - 1) + " distinct numbers from 1 to " + n);

        int[] distinct = new int[n - 1];
        int first = StdIn.readInt();
        distinct[0] = first;

        // Adds user input within range into the array, not taking duplicates
        for (int i = 1; i < n - 1; i++) {
            int current = StdIn.readInt();
            for (int j = 0; j < i; j++) {
                if (current == distinct[j]) {
                    StdOut.println("Please no duplicates.");
                    // This is the loop counter decrease with Checkstyle warning
                    i--;
                    break;
                }
                else if (current < 1 || current > n) {
                    StdOut.println("Please stay within range.");
                    // This is the loop counter decrease with Checkstyle warning
                    i--;
                    break;
                }
                else distinct[i] = current;
            }
        }
        StdOut.println();

        Arrays.sort(distinct);

        // Prints out the missing number
        if (distinct[0] != 1) StdOut.println(1 + " is the missing number!");
        else if (distinct[n - 2] != n) StdOut.println(n + " is the missing number!");
        else {
            for (int i = 0; i < n - 1; i++) {
                if (distinct[i] + 1 != distinct[i + 1]) {
                    StdOut.println((distinct[i] + 1) + " is the missing number!");
                    break;
                }
            }
        }
    }
}