a = int(raw_input())
b = int(raw_input())

menor = min(a, b)
maior = max(a, b)

total = 0
aux = 1
while True:
    if maior == menor: break
    menor += 1
    total += aux
    
    if maior == menor: break
    maior -= 1
    total += aux
    
    aux += 1
    
    print(total)

     		 		  	     			   		 		