- while
1 Bash[ | ]
![](https://z-images.s3.amazonaws.com/thumb/e/ec/Crystal_Clear_app_xmag.svg/24px-Crystal_Clear_app_xmag.svg.png 1.5x, https://z-images.s3.amazonaws.com/thumb/e/ec/Crystal_Clear_app_xmag.svg/32px-Crystal_Clear_app_xmag.svg.png 2x)
Bash
Copy
x=1
while [ $x -le 3 ]
do
echo "x = $x"
x=$(( $x + 1 ))
done
# x = 1
# x = 2
# x = 3
Bash
Copy
i=1
while [ $i -lt 4 ]
do
echo "i = $i"
i=`expr $i + 1`
done
# i = 1
# i = 2
# i = 3
2 PHP[ | ]
![](https://z-images.s3.amazonaws.com/thumb/e/ec/Crystal_Clear_app_xmag.svg/24px-Crystal_Clear_app_xmag.svg.png 1.5x, https://z-images.s3.amazonaws.com/thumb/e/ec/Crystal_Clear_app_xmag.svg/32px-Crystal_Clear_app_xmag.svg.png 2x)
PHP
Copy
$x = 1;
while($x <= 5) {
echo "[$x]";
$x += 1;
}
- alternative syntax
PHP
Copy
$x = 1;
while($x <= 5):
echo "[$x]";
$x += 1;
endwhile;
3 Python[ | ]
Python
Copy
a = 1
sum = 0
while a <= 10:
sum += a
a += 1
print(sum)
# 55
4 Perl[ | ]
Perl
Copy
my $a = 1;
my $sum = 0;
while ($a <= 10) {
$sum += $a;
$a += 1;
}
print $sum;
# 55
5 Ruby[ | ]
Ruby
Copy
i = 1
sum = 0
while i <= 10
sum += i
i += 1
end
puts sum
# 55
Ruby
Copy
i = 1
sum = 0
while i <= 10 do
sum += i
i += 1
end
puts sum
# 55