I have an array and I would like to take action on every iteration
for($i = 0; $i < count($array); $i++) {
0,1,3...10
// Execute
$create->save();
11, 12, 13... 20
// Execute
$create->save();
}
You can use the modulo of 10.
for($i = 0; $i < count($array); $i++) {
if($i%10 == 0{
$create->save();
}
}
Something like this?
$n = 10;
for($i = 0; $i < count($array); $i++) {
if($n == $i) {
$create->save();
$n = $n + 10;
}
}
But here in your loops 10 != 10, because is 11 loop. If you need to execute at every 10 loop, then $n = 9 or $i = 1;
Related
I have created an array dynamically like this way
$names = array();
for ($i = 0; $i < 100; $i++) {
$names[] = $i;
}
then created part
$parts = count($names) / 20;
and created a sub array then loop through the parts
$j = 0;
for ($i = 0; $i < $parts; $i++) {
echo "Part" . $i."<br>";
$newarray = array_slice($names, $j, 20);
for ($i = 0; $i < count($newarray); $i++) {
echo $i;
}
$j = $j + 20;
}
The problem is that this code displays from zero to 19 It doesn't display the other parts
Both the inner and outer loops use the same control variable $i, so just change the inner one...
$j = 0;
for ($i = 0; $i < $parts; $i++) {
echo "Part" . $i."<br>";
$newarray = array_slice($names, $j, 20);
for ($i1 = 0; $i1 < count($newarray); $i1++) {
echo $i1;
}
$j = $j + 20;
}
My niece is trying to create one for-loop (php), that results in this:
* 12345678910987654321
example for loop she tried:
for ($i = 1; $i <= 10; $i++ , $i = 10; $i <= 1; $i--) {
echo $i . ' ';
}
She can only use if's and elseif's. I'm not a programmer and can't really help her. Any ideas how this could be achieved in php?
Any information would be greatly appreciated.
The key is to add a variable instead of a number, then reverse that number when $i hits 10.
for($i = 1, $j = 1; $i> 0; $i+=$j) // Start i at 1, and j at 1
{
echo $i;
if($i == 10)
$j = -1; // i has hit 10, so use -1 to start subtracting
}
Another possibility is to loop up to 20, printing $i for the ascending part and 20 - $i for the descending.
for ($i = 1; $i < 20; $i++) {
if ($i <= 10) {
echo $i;
} else {
echo 20 - $i;
}
}
hi i am using php to learn algorithms, i wanted to convert this psuedocode into php,
for i = 1 to n − 1
minval = A[i]
minindex = i
for j = i to n
if (A[j] < minval)
minval = A[j]
minindex = j
exchange A[i] and A[minindex]
this the corresponding code in php
$A = array(1, 4, 2, 3, 70, 10, 7 );
$n = sizeof($A);
for ($i = 0; $i == $n - 1; $i++){
for ($j = $i + 1; $j == $n; $j++){
if ($A[$i] > $A[$j]){
$temp = $A[$j];
$A[$j] = $A[$i];
$A[$i] = $temp;
}
}
}
print_r($A);
print_r is outputting the array as its original order, why my algorithms doents reorder the array ?
You should check your forloops :
for ($i = 0; $i == $n - 1; $i++){
for ($j = $i + 1; $j == $n; $j++){
should be
for ($i = 0; $i < $n - 1; $i++){
for ($j = $i + 1; $j < $n; $j++){
As the second argument in for is a requirement to continue the loop.
I have this code, but i want in second loop a decrease of $p value. The first internal loop must be repeated three times, the second, two times and the last, one time. I am trying $p-- but without success.
Any idea ? thanks
$p = 3;
for ($i = 0; $i < 3; $i++) {
for ($o = 0; $o < $p; $o++) {
echo "something";
$p--;
}
}
Move your $p-- to outside the inner for loop:
$p = 3;
for ($i = 0; $i < 3; $i++) {
for ($o = 0; $o < $p; $o++) {
echo "something";
}
$p--;
}
Or better, just depend on the value of $i:
for ($i = 0; $i < 3; $i++) {
for ($o = 0; $o < 3 - $i; $o++) {
echo "something";
}
}
Or if you don't actually use $i:
for ($i = 2; $i >= 0; $i--) {
for ($o = 0; $o < $i; $o++) {
echo "something";
}
}
It's quite simple.
for ($i = 2; $i >= 0; $i--)
{
}
Set the starting number at the upper limit number, and then go down until equal to 0, $i minus 1;
You need to decrement $p outside the first loop
Say I create a recursive array with this code:
$digits = 0;
$tens = 0;
$hundreds = 0;
for($i = 0; $i <= 100; $i++)
{
$myArray[$hundreds][$tens][$digits] = $i;
$digits++;
if($digits > 9)
{
$digits = 0;
$tens++;
}
if($tens > 9)
{
$tens = 0;
$hundreds++;
}
}
how could I echo out all the data fromt the 'tens array' == 2?
To be clear, I'd be looking for these results:
20 21 22 23 24 25 26 27 28 29
since im using base 10, I could just do this:
for($i=0; $i < 10; $i++)
{
echo $myArray[0][2][$i]
}
but what if i have no idea how many elements are in the digits array?
foreach($myArray[0][2] as $v) {
echo $v."<br>\n";
}
<?php
$tensArr = $myArray[0][2];
for($i= 0 ; $i < count($tensArr); $i++)
{
echo $tensArr[$i]."\n" ;
}