PROGRAMMING:Count the number of words

Please write a program, input a paragraph of text (end with carriage return), count the number of words and output.
Note: here a word is defined as a continuous string of letters.
####Input format:
>A paragraph of text
####Output format:
>Number of words
####Input sample 1
```in
My name's Catherine Flower.
```
####Output sample 1
```out
five
```
####Input sample 2
```in
I = U / R
```
####Output sample 2
```out
three
```







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