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Readability settings Prev Up Next Scratch ActiveCode Profile title here \(
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Section 7.6 Looping and counting
The following program counts the number of times the letter “r” appears in a string:
This program demonstrates another pattern of computation called a
counter . The variable
count is initialized to 0 and then incremented each time an “r” is found. When the loop exits,
count contains the result: the total number of rs.
Activity 7.6.1 .
11-9-2: What is printed by the following:
s = "peanut butter"
count = 0
for char in s:
if char == "t":
count = count + 1
print(count)
0
Incorrect! count is initialized to 0, but is then incremented by the for loop. Try again.
3
Correct! The letter t appears 3 times in "peanut butter".
4
Incorrect! The value of count is initially 0, not 1. Try again.
Nothing, this is an infinite loop
Incorrect! This for loop will eventually terminate because string s has a finite number of characters. Try again.
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