All subsequence of array print logic

#include<bits/stdc++.h>
using namespace std;

int main()
{
int n;
cin>>n;
int a[n];
for(int i=1;i<=n;i++)
cin>>a[i];

for(int i=n;i>0;i--){
for(int k=0;k<=n-i;k++){
for(int j=k;j<i+k;j++){
cout<<a[j]<<" ";
}
cout<<endl;
}
}
}