Subarray with 0 sum

PROBLEM :

Given an array of positive and negative numbers, find if there is a subarray (of size at-least one) with 0 sum.

Input:
The first line of input contains an integer T denoting the number of test cases. Then T test cases follow. Each test case contains an integer n denoting the size of the array. The next line contains n space separated integers forming the array.

Output:
Print "Yes" ( without quotes) if there exist a subarray of size at least one with sum equal to 0 or else print "No" ( without quotes).

Constraints:
1<=T<=100
1<=n<=10^4
-10^5<=a[i]<=10^5

Example:
Input:
2
5
4 2 -3 1 6
5
4 2 0 1 6

Output:
Yes
Yes
       
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SIMPLE c++ IMPLEMENTATION :
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#include<iostream>
#include <bits/stdc++.h>
#include<unordered_set>
using namespace std;
int main()
{
int t ;
cin>>t ;
while(t--)
{
   int no ;
   cin>>no ;
 
   int arr[no] ;
   for(int i=0;i<no;i++)
       cin>>arr[i] ;
     
   unordered_set<int> set ;
 
   int sum=0 ;
   bool flag=false ;
 
   for(int i=0;i<no;i++)
   {
       sum+=arr[i] ;
     
       if(sum==0||set.find(sum)!=set.end())
       {
           flag=true ;
           break ;
       }
       else
           set.insert(sum) ;
   }
 
   if(flag)
       cout<<"Yes" ;
   else
       cout<<"No" ;
  cout<<endl ;
}
return 0;
}

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