import os
def func(x):
return pow(x,2)#Function-->f(x)
#integral
a=int(input("lower limit: "))
b=int(input("upper limit: "))
#Riemann sums
for n in range(1,pow(10,9)):#n sonsuza yaklaşırken
delta_x=(b-a)/n
val=0
for i in range(0,n):
val+=func(a+i*delta_x)*delta_x
print(val)
#Riemann sums
#result
os.system("cls")
print(round(val,2))#Approximate Value