a=input("enter a number:    ")
b=input("enter a number:    ")
a=eval(a)
b=eval(b)
print(a+b)

a=input("enter a number:")
b=input("enter a number:")
c=input("enter a third number:")
a=eval(a)
b=eval(b)
c=eval(c)
print(a+b+c)
