Loops in Perl
In this tutorial, we will learn about different types of loops in Perl. We will cover the basics of for, while, and do-while loops.
What is a Loop
A loop is a control flow statement that allows code to be executed repeatedly based on a condition.
Perl supports three types of loops: for loops, while loops, and do-while loops.
For Loop
A for loop (also known as a foreach loop in Perl) is used when the number of iterations is known before entering the loop. The syntax for the for loop is:
for (initialization; condition; increment) {
# Code block to be executed
}
While Loop
A while loop is used when the number of iterations is not known beforehand. The syntax for the while loop is:
while (condition) {
# Code block to be executed
}
Do-While Loop
A do-while loop is similar to a while loop, but it guarantees that the code block will be executed at least once. The syntax for the do-while loop is:
do {
# Code block to be executed
} while (condition);
Example 1: Printing Numbers from 1 to 10 using For Loop
- Declare an integer variable
$i
. - Use a for loop to print numbers from 1 to 10.
Perl Program
for (my $i = 1; $i <= 10; $i++) {
print "$i ";
}
Output
1 2 3 4 5 6 7 8 9 10
Example 2: Printing Numbers from 1 to 5 using While Loop
- Declare an integer variable
$i
and initialize it to 1. - Use a while loop to print numbers from 1 to 5.
Perl Program
my $i = 1;
while ($i <= 5) {
print "$i ";
$i++;
}
Output
1 2 3 4 5
Example 3: Printing Numbers from 1 to 3 using Do-While Loop
- Declare an integer variable
$i
and initialize it to 1. - Use a do-while loop to print numbers from 1 to 3.
Perl Program
my $i = 1;
do {
print "$i ";
$i++;
} while ($i <= 3);
Output
1 2 3