http://noi.openjudge.cn/ch0111/08/

"""
1.11 编程基础之二分查找 08 不重复地输出数
http://noi.openjudge.cn/ch0111/08/

Python字符串去重
https://www.jianshu.com/p/b9162f389b5c

https://www.cnblogs.com/zhenghiber/p/15110871.html

Python：对输入的单词进行字典序排序输出
https://www.cnblogs.com/JodieRao/p/12635910.html

Python 程序按字母顺序对单词进行排序
https://www.nhooo.com/python/python-examples-alphabetical-order.html

"""

n=int(input())

a=list(map(int,input().split()))

a.sort()

b=[]

for word in a:
            
            if not word in b:
                        
                        b.append(word)

for i in b:
            print(i,end=' ')

C++代码

/*
1245：不重复地输出数
http://ybt.ssoier.cn:8088/problem_show.php?pid=1245

1.11编程基础之二分查找_08不重复地输出数
http://noi.openjudge.cn/ch0111/08/
*/
#include<iostream>
#include<cstdio>
#include<cstdlib>
#include<cstring>
#include<cmath>
#include<algorithm>
#include<string>
#define INF 999999999
#define N 1000001
#define MOD 1000000007
#define E 1e-3
using namespace std;
int a[N];
int main( void )
{
    int n;
    
    cin>>n;
    for(int i=1;i<=n;i++)
        cin>>a[i];
        
    sort(a+1,a+1+n);
    
    cout<<a[1];
    for(int i=2;i<=n;i++)
        if(a[i]!=a[i-1])
            cout<<" "<<a[i];
    cout<<endl;
    
    return 0;
}