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Given the following text description, write Python code to implement the functionality described.
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Description:
Maximum count of Equilateral Triangles that can be formed within given Equilateral Triangle
Function to find the number of equilateral triangle formed within another triangle ; Check for the valid condition ; Number of triangles having upward peak ; Number of inverted triangles ; Total no . of K sized triangle ; Driver Code ; Given N and K ; Function Call

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Python Code:
def No_of_Triangle(N , K ) : 
	 if(N < K ) : 
	 return - 1 ; 
  else : 
	 Tri_up = 0 ; 
 Tri_up =(( N - K + 1 ) *(N - K + 2 ) ) // 2 ; 
 Tri_down = 0 ; 
 Tri_down =(( N - 2 * K + 1 ) *(N - 2 * K + 2 ) ) // 2 ; 
 return Tri_up + Tri_down ; 
   if __name__== ' __main __' : 
	 N = 4 ; K = 2 ; 
 print(No_of_Triangle(N , K ) ) ; 
 
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