Chapter 4 (pp. 95–132) of Computer Science I.

Topics

Section	Page	Content
While Loops	97	Condition-first iteration.
For Loops	99	Counter-based iteration.
Do-While Loops	100	Execute-then-test.
Foreach Loops	102	Collection iteration.
Other Issues	103	Nested loops, infinite loops, common errors, equivalency of loops.
Problem Solving With Loops	106	Applying iteration to problems.
Examples	107	For vs While, Primality Testing, Paying the Piper.

Key Ideas

All loop forms are equivalent in expressive power; choice is stylistic/clarity.
Infinite loops and off-by-one errors are the classic failure modes.
Paying the Piper and nested-loop examples recur across language parts.
Foreach ties into arrays & collections.

sum ← 0
i ← 1
while i ≤ n:
  sum ← sum + i
  i ← i + 1

Accumulates 1..n.

fact ← 1
for i from 2 to n:
  fact ← fact × i

The same result as a while loop — loop forms are equivalent.

int sum = 0;
for (int i = 1; i <= n; i++)   // sum 1..n
    sum += i;

long fact = 1;
for (int i = 2; i <= n; i++)   // n!
    fact *= i;

[1] Computer Science I, Ch. 4, pp. 95–132.