Question

1. In *PERL* Use a loop structure and code a program that produces the following output (Take one parameter to let user specify how many lines need to be printed):

A
AA
AAA
AAAB

AAABA

AAABAA

AAABAAA

AAABAAAB

Answer 1

Executable Perl Code:

# Number of A in a block
$numA = 3;

# Number of B in a block
$numB = 1;

# Variable for loop
$val_i = 1;

# Output
$out = "";

# Variable for loop
$val_j = 1;

# Number of space to be printed
$spaceAvail=0;

# Loop for number of lines
while ($val_i <= $ARGV[0])
{
while ($val_j <= $val_i)
{
# Whwn new block starts
if ($numA == 0 && $numB == 0)
{
$numA = 3;
$numB = 1;
}
# Output A
if ($numA > 0)
{
$out.= "A";
$numA--;
}
# Output B
else
{
$out.= "B";
$numB--;
$spaceAvail++;
}
$val_j++;
}
# Print output
print($out . "\n");
  
# Print required spaces
for (my $i=0; $i <$spaceAvail; $i++) {
print(" ");
}
$val_i++;
}