题解 | #迭代器遍历set#

#include<bits/stdc++.h>
#include <iostream>
using namespace std;
int main() {
    set<int>s;
    // write your code here......
    int a;
    while (cin >> a) {
        s.insert(a);
    }

    set<int>::iterator iter = s.begin();
    while (iter != s.end()) {
        cout << *iter << " ";
        iter++;
    }

	cout<<endl;

    while (iter != s.end()) {
        iter--;
        cout << *iter << " ";
    }
	
	cout<<endl;

    return 0;
}