Running for loop inside other for loop - php

Can anyone help me understand why a variable takes its initial value after incrementing the variable? below is code:
$k= 0;
$l= 3;
for($i = 0; $i<3; $i++){
for($j = $k; $j<$l; $j++){
echo $j;
}
echo $k+3;
echo $l+3;
}
In this we have two for loops running one inside other. Here we run three times the outside for loop, inside this we are running other for loop again. The problem we are facing is that when inner for loop end we have incremented $k and $l both by 3 but it always take value 0 and 3 respectively.

we have incremented $k and $l both by 3
Nope, you only print the result of your values plus 3, but you do not set them anywhere in the loop:
Instead of
echo $k+3;
echo $l+3;
write
$k = $k + 3;
$l = $l + 3;

You should try removing the "echo" and incrementing the variable in each loop. Then print them out after.

Try this:
<?php
$k= 0;
$l= 3;
for($i = 0; $i<3; $i++){
for($j = $k; $j<$l; $j++){
$j = $j++;
}
$k = $k+3;
$l = $l+3;
}
echo $k.'<br>';
echo $l;
?>
Gives you:
9
12

TRY this.
$k += 3;
$l += 3;
echo $k;
echo $l;

Try This
$k= 0;
$l= 3;
for($i = 0; $i<3; $i++){
for($j = $k; $j<$l; $j++){
echo $j;
}
$k = $k+3;
$l = $l+3;
}
echo $k.'<br>';
echo $l;
First Increment the value and store it in the variable
$k = $k+3;
$l = $l+3;
Then You need to print using
echo $k.'<br>';
echo $l;

#Harinarayan First of all you need to read about echo() http://php.net/manual/en/function.echo.php
echo — Output one or more strings
echo does not manipulate expression as you did in your question like:
echo $k+3;
instead of using echo for the increment you should first increment the variable and then echo that variable like below:
<?php
$k= 0;
$l= 3;
for($i = 0; $i<3; $i++){
for($j = $k; $j<$l; $j++){
echo $j;
}
$k += 3;
$l += 3;
echo $k;
echo "<br>";
echo $l;
}

Related

how to display cycles in php added elements to each cycle in php?

I need your help to solve this problem, I am trying to write the necessary code so that the output is as follows:
PHP! PHP!! PHP!!! PHP!!!! PHP!!!!!
<?php
$y = ['!'];
for($i = 1; $i <= 5; $i++)
{
print "PHP!"."$y\t";
if($y+1 <5)
$y="!";
$y+'!';
}
?>
Until the second word, it adds one more exclamation point and in the rest of the repetitions it has the same number, that is two exclamation points.
How can I solve this problem?
Try this:
<?php
for ($i = 0; $i < 5; $i++) {
echo "PHP".str_repeat ("!", $i);
}
?>
You can try it:
<?php
for($i = 1; $i <= 5; $i++)
{
echo "PHP";
for($j = 1; $j <= $i; $j++){
echo "!";
}
}
?>
You can also use str_repeat():
<?php
for ($i = 1; $i <= 5; $i++) {
echo "PHP".str_repeat ("!", $i);
}
?>
Output will be: PHP!PHP!!PHP!!!PHP!!!!PHP!!!!!

Write a PHP code to print following number pattern

Write a PHP code to print following number pattern:
147
258
369
I am trying like this but its shows me shows below. how to convert column to row pattern.
<?php
$num = "";
for($i=1;$i<=9;$i++) {
$num .= $i;
if($i%3==0){
$num .="<br />";
}
}
echo $num;
?>
please help me
You need to use for loop inside for loop to achieve this. Below is the code
$num = "";
for( $i = 1; $i <= 3; $i++ ) {
for( $j = 0; $j <= 2; $j++) {
$k = $i + ( $j * 3 );
$num .= $k;
}
$num .= "<br />";
}
echo $num;
Here is another way to get this output.
for($i = 1; $i <= 3; $i++) {
$print = $i;
for($j = 1; $j <= 3; $j++) {
echo $print;
$print = $print + 3;
}
echo "<br />";
}

PHP Array, Get every 4 results and output in a loop

I'm trying to output my array results in groups of 4.
<?php for ($i = 0; $i < 4; ++$i) { ?>
<div>
// code
</div>
<?php } ?>
The above does 4, but obviously doesn't re-loop.
You can loop whole array and group you output with help of "%" operator.
<div>
<?php for ($i = 0; $i < count($array); $i++) {
if (($i % 4) == 0) {
echo "</div><div>";
}
echo "Element " . $array[$i]; // CODE
}
</div>
Other than using Mod as the other answers show, you could use array_chunk() to create the groups:
$groups = array_chunk($original_array, 4);
foreach($groups as $group){
echo '<div>';
foreach($group as $item){
echo $item;
}
echo '</div>';
}
You can use a while loop to reloop for the whole results to be printed
<?php while(conditions) {
for ($i = 0; $i < 4; ++$i) { ?>
<div>
// code
</div>
<?php } } ?>
Try this that way you can jump by 4
for ($i = 0; $i < 20; $i = $i+4) {
echo $i.'<br/>';
}
I would use a foreach and then just throw in an extra check to output the divs.
$i=0;
foreach ($array as $key->$val)
{
if($i%3==0)
{
echo "<div>";
}
// your stuff
if($i%3==0)
{
echo "</div>";
}
$i++;
}
array_slice() returns the sequence of elements from the array array as specified by the offset and length parameters.
you can check out from here http://php.net/manual/en/function.array-slice.php
try this, use nested for loop, this will loop 4 times. You can try to integrate with your code. If
for ($i = 0; $i < 4; $i++){
for($j = 0; $j < 4; $j++){
echo $a[$j++];
}
echo "<br/>";
}
I hope it can help you.
you can try $i++, because you use ++$i in this way "for" works 3 times!
for ($i = 0; $i < 4; $i++)

add in loop in multi dimensional array

i am facing a problem
can some one suggest me
for ($i = 1; $i <= 2; $i++) {
$r2 = 0;
for ($t = 1; $t <= 2; $t++) {
echo $r2;
$r2++
}
}
output is 0101;
can i get output 0123 ??? please
if
for ($i = 1; $i <= 3; $i++) {
$r2 = 0;
for ($t = 1; $t <= 3; $t++) {
echo $r2;
$r2++
}
}
output is 010101;
can output 012345678 ??? please
and if
for ($i = 1; $i <= 4; $i++) {
$r2 = 0;
for ($t = 1; $t <= 4; $t++) {
echo $r2;
$r2++
}
}
output is 01010101;
can output 0123456789101112131415 ??? please
i think you understand
thanks
In all of these cases you are initializing $r2=0; in the inner loop. It should be outside the loop.
$r2=0;
for($i=1;$i<=2;$i++){
for($t=1;$t<=2;$t++){
echo $r2;
$r2++
}
}
This would produce "1234".
why are you using two nested for loops ?
why not just use one:
for ($i=0; $i<=15; $i++) echo $i . " ";
Try this:
$r2 = 10;
for($t = 0; $t <= $r2; $t++){
echo $r2;
}
Oh wait.. I get it now, why you have the two nested loops, you want to essentially raise a number to the power of 2 in order to control the number of values output. In that case, what you want is simply this:
// this is the variable you need to change to affect the number of values outputed
$n = 2;
// Square $n
$m = $n * $n;
// Loop $m times
for ($i = 0; $i < $m; $i++) {
echo $i;
}

How to kickout in a foreach loop?

For example in a for loop you can kick out like this:
for($i = 0; $i < count($ary); $i++){
if($ary[$i] == 'blah')
$i = count($ary);
echo $i;
}
Or in a while loop:
$i = 0;
while($i < count($ary)){
if($ary[$i++] == 'blah')
$i = count($ary);
echo $i;
}
Not sure really what you mean by "kick out", but:
To skip to the next item, use continue;
To stop the entire loop, use break;
If I understand your question correctly what you are looking for is the break keyword.
PHP Break
Use break
for($i = 0; $i < count($ary); $i++){
if($ary[$i] == 'blah')
break;
echo $i;
}
for($i = 0; $i < count($ary); $i++){
if($ary[$i] == 'blah')
break;
echo $i;
}
foreach($ary as $c){
if($c=='blah')break;
}
Manual

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