if and while blocks

'''
a=5
b=10
if a < b:
    print(a, "is smaller thant", b)
elif a > b:
    print (a, " is bigger than ", b)
else:
    print (a, "is equal to ",b)
'''

def getGrade():
    grade=-1
    while grade < 0 or grade > 100:
        grade=int(input("Enter a grade between 0 and 100 "))
    #if grade < 0 or grade > 100:
        #grade=-1       
    return grade
                    
def evaluateGrade():
    g = getGrade()
    #if g == -1:
        #print ("Invalid Grade")
        #return
       
    if g > 90:
        print("you did great")
    elif g > 80:
        print(" you did good")
    elif g > 70:
        print("you passed")
    else:
        print("Sorry, you failed.")

def main():
    choice='y'
    while choice == 'y':
        evaluateGrade()
        choice=input("y to continue")
        choice.lower()

main()