Iterative Subset Generation

//Iterative Subset Generation
#include <bits/stdc++.h>
#include <ext/pb_ds/assoc_container.hpp>

using namespace __gnu_pbds;
using namespace std;
typedef long long ll;

#define mem(dp,a)           memset(dp,a,sizeof dp)
#define rep(i,a,b)          for(ll i=a;i<b;i++)
#define pb(x)               push_back(x)
#define mp(x,y)             make_pair(x,y)
#define fastio              ios_base::sync_with_stdio(false);cin.tie(NULL)
#define F                   first
#define S                   second
#define all(v)              (v).begin(),(v).end()
#define pi                  3.14159265359
ll INF=1e18+10;
ll MOD=1000000007;

const int N=10;int n;
int a[N];

int main()
{
    cin>>n;
    rep(i,0,n)cin>>a[i];
    rep(i,0,(1<<n))
    {
        rep(j,0,n)
        if(i&(1<<j))
            cout<<a[j]<<" ";
        cout<<endl;
    }
}