get input for array of unknown length 2fsize in c 2b 2b

1#include<iostream>
2#include<sstream>
3
4using namespace std;
5
6int main()
7{
8	string s;
9    getline(cin, s);
10    
11    int data
12    istringstream iss(s);
13    while(iss>>data)
14    	cout<<data<<" ";
15	return 0;
16}