# Print all Subsequences of an Array Using C++

This Project Prints all the Subsequences of the Array.Input will be given by User i.e.., an Array and Size of Array 'N' using C++ programming language.

Given an integer array of unique elements By User.

Have to print all the Subsequences of the array.

The Subsequences must not contain duplicate

Example 1:

```Input: a = [1,2,3],N=3
Output: [[],[1],[2],[1,2],[3],[1,3],[2,3],[1,2,3]]
```

Example 2:

```Input: a= [0],N=1
Output: [[],[0]]```
```#include
#include<bits/stdc++.h>
using namespace std;
class Solution {
public:
void fun(int ind,vector<vector>&result,vector&ans,int n,vector&a)
{
if(ind==n)
{
result.push_back(ans);
return ;
}
ans.push_back(a[ind]);
fun(ind+1,result,ans,n,a);
ans.pop_back();
fun(ind+1,result,ans,n,a);

}
vector<vector> SubSequences(vector&a) {
vector<vector>result;
int n=a.size();
vectorans;
fun(0,result,ans,n,a);
sort(result.begin(),result.end());
return result;
}
};
int main()
{
// Let us take vector a sample input
vectora;
int n=3;
a.push_back(1);
a.push_back(2);
a.push_back(3);
Solution obj; // creation of obj
vector<vector>ans=obj.SubSequences(a);
for(int i=0;i<ans.size();i++)
{
for(int j=0;j<ans[i].size();j++)
{
cout<<ans[i][j]<<" ";
}
cout<<endl;
}
return 0;
}
```

Constraints:

• `1 <=size of array<= 10`
• all the elements in array are unique given by the User.