#  avg_word_length
#    given a sentence, calculate the average word length

import string  # include string library for the split function.

def main():
    print "Given input sentence, determine avg. word length"
    lettersum = 0.
    wordcount = 0.
    textin = raw_input("Enter sentence : ")
    for word in string.split(textin):
        numltrs = len(word)
        if (word[-1] == "." or
        word[-1] == ";" or
        word[-1] == ":" or
        word[-1] == "!" or
        word[-1] == "?" or
        word[-1] == ",") :
            numltrs = numltrs-1
        lettersum = lettersum + numltrs
        wordcount = wordcount + 1.0
    print "The average word length is ",lettersum/wordcount
main()