6.6: Looping and Counting
- Page ID
- 3093
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The following program counts the number of times the letter a
appears in a string:
Code 6.6.1 (Python)
This program demonstrates another pattern of computation called a counter. The variable count
is initialized to 0 and then incremented each time an a
is found. When the loop exits, count
contains the result: the total number of a
's.
Exercise 3:
Encapsulate this code in a function named count
, and generalize it so that it accepts the string and the letter as arguments.