qkF3rM - Online C++0x Compiler & Debugging Tool

#include <iostream>
#include <vector>
#include <set>
#include <ctime>
#include <string.h>
using namespace std;

int main() {
	string text;
	getline(cin, text);
	set<char> see;
	set<char> dupl;
	for(char s : text){
		if(see.find(s) != see.end()){
			dupl.insert(s);
		}
		else{
			see.insert(s);
		}
	}
	set<char>::iterator it;
	for(it = dupl.begin(); it != dupl.end(); it++){
    	cout << *it << " ";
	}
	cout<<endl;
	return 0;
}