Problem Statement 
 You are given three positive integers, X, Y and P. Return the least sum of two positive integers a and b such that P is a divisor of a*X+b*Y. 

Definition 
 Class:  TheEquation  Method:  leastSum  Parameters:  int, int, int  Returns:  int  Method signature:  int leastSum(int X, int Y, int P)  (be sure your method is public) 




Notes 
  The answer is never greater than 2*P: if a = P and b = P, then P is definitely a divisor of a*X+b*Y. 

Constraints 
  X, Y and P will each be between 1 and 1000, inclusive. 

Examples 
0)  
  Returns: 3  When a=2 and b=1, a*X+b*Y is 10, which is a multiple of P=5. No other valid pair of values for a and b has a smaller sum. 


1)  
  Returns: 2  Don't forget that a and b must be positive. 


2)  
 
3)  
 
4)  
 