xor of three primes is zero

# Python 3 program to count the number of 
# unique triplets whose XOR is 0 
  
# function to count the number of  
# unique triplets whose xor is 0 
def countTriplets(a, n): 
      
    # To store values that are present 
    s = set() 
    for i in range(n): 
        s.add(a[i]) 
      
    # stores the count of unique triplets 
    count = 0
      
    # traverse for all i, j pairs such that j>i 
    for i in range(n): 
        for j in range(i + 1, n, 1): 
              
            # xor of a[i] and a[j] 
            xr = a[i] ^ a[j] 
              
            # if xr of two numbers is present, 
            # then increase the count 
            if (xr in s and xr != a[i] and 
                            xr != a[j]): 
                count += 1; 
          
    # returns answer 
    return int(count / 3) 
  
# Driver code 
if __name__ == '__main__': 
    a = [1, 3, 5, 10, 14, 15] 
    n = len(a)  
    print(countTriplets(a, n))  
      
# This code is contributed by 
# Surendra_Gangwar