from cs50 import get_string

# initializing default values for variables
letters = 0
words = 1
sentences = 0

# getting string from user and looping through each character
user_input = get_string("Text:")
n = len(user_input)

for i in range(n):
    ascii_code = ord(user_input[i])
    # counting letters based on ascii values from a-z & A-Z
    if 65 <= ascii_code <= 122:
        letters += 1
    # counting words based on ascii value for space
    elif ascii_code == 32:
        words += 1
    # counting sentences based on ascii value for ".","!","?"
    elif ascii_code == 33 or ascii_code == 63 or ascii_code == 46:
        sentences += 1
# calculating Coleman-Liau index
let = letters / words * 100
s = sentences / words * 100
index = round(0.0588 * let - 0.296 * s - 15.8)

if index < 1:
    print("Before Grade 1")
elif index >= 16:
    print("Grade 16+")
else:
    print("Grade " + str(index))