COMP111 : Quiz 5
Perl Programming


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1) What is the value of $n after the following Perl statements are executed?
 
	$n = 0;
	if(!$n){
		$n = $n + 1;
	}
	if($n){
		$n = -$n;
	}
	$n = $n + 1;


Answer:  0



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2) What is the value of $n after the following Perl statements are executed?

 	$n = 1; $a=4; $b=8; $c=19;
	if($b>10 && $c<4 || $a==0){
		$n = $n + 2;
	}
	if($a < 10 || $b>5 && $c<9){
		$n = $n + 3;
	}
	if($c>11 && $a<2 || $b==8){
		$n = $n + 4;
	}


Answer:  8


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3) What is the value of $n after the following Perl statements are executed?

	$n = 4;
	@a = (1,2,3);
	while ( $n <= 13 ){
		$n += $a[$n%3];
	}


Answer:  15


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4) What is the value of $n after the following Perl statements are executed?

	$n = 4;
	@a = (1 ..3);
	for($i=1; $i<=$#a; $i++){
		$n += $a[$i-1];
	}


Answer:  10
Because for(i=0; i<=2; i++)
indices a[-1] a[0] a[1]


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5) What is the value of @a after the following Perl statements are executed?

	$n = 4;
	@a = 2;
	for($i=1; $i<=3; $i++){
		$a[$i] = $n;
		$n--;
	}


Answer:  2 4 3 2


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6) What is the value of @a after the following Perl statements are executed?

	$n = 4;
	@a = 2;
	@b = (5,$n,7,@a);
	($n,@a) = @b;


Answer:  4 7 2



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7) What is the value of @a after the following Perl statements are executed?

	$n = 5;
	@a = 9;
	@b = ($n,7,@a,4);
	($n,@a) = (@b[3,2,1],$n);


Answer:  9 7 5