Subset Sum Easy problem doubt

#1

Question: Mike is a very passionate about sets. Lately, he is busy solving one of the problems on sets. He has to find whether if the sum of any of the non-empty subsets of the set A is zero.If the sum of any of the subset is zero, then print “Yes” (without quotes) else print “No”(without quotes).

I am having problem in implementation of recursive approach-- Please explain how to proceed.
I have tried my code but it is giving wrong answer. Please point out my mistake and please suggest ways how to think and proceed with such recursive problems

#include
using namespace std;
bool subsetsum(int*,int*,int,int,int);
int main() {
int t,n;
cin>>t;
while(t–)
{
cin>>n;
int* arr=new int[n];
int* oarr=new int[n];//to store the subset elements
for(int i=0;i<n;i++)
cin>>arr[i];
bool res=subsetsum(arr,oarr,0,0,n);
if(res==true)
cout<<“No”;
else
cout<<“Yes”;
}
return 0;
}
bool subsetsum(int* arr,int* oarr,int i,int j,int n)
{
if(i==n)//when i pointer reaches the last element return true ie No
{
int ans=0;
for(int k=0;k<j;k++)
ans=ans+oarr[k];
if(ans==0)
return false;
else
return true;
}
int ans=0;
for(int k=0;k<j;k++)
ans=ans+oarr[k];
if(j!=0 && ans==0){
return false;
}//when sum is 0 return false ie Yes
oarr[j]=arr[i];
subsetsum(arr,oarr,i+1,j+1,n);//when subset sum includes the current element
subsetsum(arr,oarr,i+1,j,n);//when subset sum excludes the current element
}

#2

there are many things first of all copy the code on online ide (https://ide.codingblocks.com), save it and share the corresponding link with you. then only it will be easier for us to clear your doubt.

  1. subsetsum(arr,oarr,i+1,j+1,n);//when subset sum includes the current element
    subsetsum(arr,oarr,i+1,j,n);//when subset sum excludes the current element

I think here you should return something

  1. for(int k=0;k<j;k++)
    ans=ans+oarr[k];
    this is doing nothing , it is just adding j numbers of array

  2. this is the modified code `#include

using namespace std;
bool subsetsum(int*,int,int,int);
int main() {
int t,n;
cin>>t;
while(–t)
{
cin>>n;
int* arr=new int[n];
// int* oarr=new int[n];//to store the subset elements

	for(int i=0;i<n;i++)
	cin>>arr[i];
	bool res=subsetsum(arr,0,0,n);
	if(res==true)
	cout<<"Yes";
	else
	cout<<"No";
}
return 0;

}

bool subsetsum(int* arr,int sum,int i,int n)
{
if(i==(n-1))//when i pointer reaches the last element return true ie No
{
int ans=0;
ans = sum+arr[i];
if(ans==0)
return true;
else
return false;
}
int ans=0;
ans = sum+arr[i];
if(ans == 0){
return true;
}
//when sum is 0 return false ie Yes

return subsetsum(arr,ans,i+1,n)||subsetsum(arr,sum,i+1,n);//when subset sum excludes the current element

}`