Main.java

import java.util.*;

class Main {
  
  public static int getDup(String[] arr) {
        int totalDup = 0;
        for (int i = 0; i < arr.length; i++) {
            int count = 0;
            for (int j = 0; j < arr.length; j++) {
                if(arr[i].equals(arr[j])){
                    count++;
                }
            }
            if (1<count){
            totalDup++;// += count;
            }
        }
        return totalDup;
  }

  public static void main(String[] args) {
      Scanner in = new Scanner(System.in);
      String [] strs = new String[in.nextInt()];
      for(int i=0; i < strs.length; i++) {
        strs[i] = in.next();
      }

    System.out.println(getDup(strs));

  } 

}