The document discusses for loops, including their general form, examples, and variations. It describes how for loops allow initialization of a counter, testing the counter value, and incrementing/decrementing the counter each iteration. The break and continue statements are also covered, with break exiting the entire loop and continue skipping to the next iteration.

1. Lecture 6
Version 1.0
The for Loop
The break Statement
The continue Statement
Version 1.0

2. Rushdi Shams, Dept of CSE, KUET, Bangladesh2
The for Loop
 The for loop allows us to specify three
things in a single line:
1. Setting a loop counter to an initial value.
2. Testing the loop counter to determine whether its value has
reached the number of repetitions desired.
3. Increasing/decreasing the value of loop counter each time the
program segment within the loop is executed.

3. Rushdi Shams, Dept of CSE, KUET, Bangladesh3
General form of for loop

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Example of for loop
 This program prints number 1 to 10

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Structure of for loop

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Variation of for loop

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Variation of for loop

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Variation of for loop

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Variation of for loop: Infinite
loop

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Observing for loops
The initialization, loop-continuation
condition and increment/decrement can
contain arithmetic expressions. Assume
that x=2 and y=10. The statement-
for(j=x; j<=4*x*y; j=j+y/x)
is equivalent to-
for(j=2; j<=80; j=j+5)

11. Rushdi Shams, Dept of CSE, KUET, Bangladesh11
Observing for loops
There can be a decrement as well (or you
can say a negative increment). For
example-

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Observing for loops
If the loop continuation condition is initially
false, the body portion of the loop is not
performed.

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Observing for loops

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Qs

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Nested for loops

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Output

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What will be the output?

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What will be the output?

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The break Statement
 We often come across situations where
we want to jump out of a loop instantly,
without waiting to get back to the
conditional test.
 The keyword break allows us to do
this.

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The break Statement
 When break is encountered inside any
loop, control automatically passes to the
first statement after the loop.

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The break Statement

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The continue Statement
 In some programming situations we
want to take the control to the beginning
of the loop, bypassing the statements
inside the loop, which have not yet
been executed.

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The continue Statement
 The keyword continue allows us to do
this. When continue is encountered
inside any loop, control automatically
passes to the beginning of the loop.

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The continue Statement