4. Loops

for loops

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Reading 1

The counting pattern

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for (init; condition; step) { body } is built for counting.

A common form is for (int i = 0; i < n; i++) which runs the body n times with i = 0, 1, ..., n-1.

You can count upward or downward. Keep the three pieces clear: start, stop rule, and how i changes.

for (int i = 0; i < 5; i++) {
    cout << i << endl;
}

for (int i = 5; i >= 1; i--) {
    cout << i << endl;
}

Check 2

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How many times does for (int i = 1; i <= 4; i++) run?

Fill in 3

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Try it 4

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This prints even numbers. Try changing the upper bound.

main.cpp

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Program input (stdin)

Output will appear here.

Assignment 5

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Read an integer n (n >= 1). Print the sum of integers from 1 through n.

main.cpp

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