判断是否有重复的数字

import java.util.Scanner; 
import java.util.HashMap; 
public class Main { 

public static void main(String[] args) { 
Scanner input = new Scanner(System.in); 
int m=input.nextInt(); 
HashMap map=new HashMap(); 
while(m-->0) { 
int tmp=input.nextInt(); 
if(map.containsKey(tmp)) { 
System.out.print(true); 
return; 
} 
map.put(tmp, true); 
} 
System.out.print(false); 

} 
}