Exercise 4: Function Write a function named word_count that accepts a string as its parameter and returns the number of words in the string. A word is a sequence of one or more non-space characters (any character other than ' '). For example, the call of word_count("hello, how are you?") should return 4. Constraints: Do not use any data structures such as arrays to help you solve this problem. Do not use the String function explode on this problem. But you can declare as many simple variables like Integer, String, etc. as you like.

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