PHP variable in loop refuses to increment - php

for($j = 0; $j < 12; $j++) {
for($k = 0; $k < 8; $k++) {
$ln = $k + 1;
if(...) {
//Code for table edges like row and col names
//end code
} else { //Other cases
//switch statement, looks like
switch($j) {
case 2:
$keyname = $ln.'_FAR_INT';
break;
... //All cases are accounted for in this switch
}
foreach($data as $key => $val) {
if(strpos($keyname, $key) !== false) {
$cellVal = $key;
break;
} else {
$cellVal = '';
}
}
}
}
}
So the problem here is that the variable $ln is stuck at 2 no matter what as soon as it hits a blank row. The first two columns have data from a database, and the third onwards have blanks in their relevant key/value pairs, so they're not returning null, but
If you notice, it gets to 2_FAR_INT, then does that forever until it hits the next row.
I don't know why it does this and debugging it has been a painful endeavor.
Dataset: Looks like {data: 1_FAR_INT, 2_FAR_INT, 3_FAR_INT, etc..., 1_TOTAL_BORN, 2_TOTAL_BORN, 3_TOTAL_BORN,...}
Why does $ln refuse to increment appropriately to $k + 1 in every single case no matter what I tell it to do?

Related

I am trying to get number of occurrences of a charaters in a string

Below is the code i tried, where count is showing improper.
Please help me to get where i am missing the logic.
I am attaching the code which i have tried so far.
PS Note:- I am not intended to use more built in function of php and so I created function for string length.
error_reporting(E_ALL);
$string = "ssddk";
function checkString($addinString, &$stringBK) {
if (empty(count($stringBK))) {
$stringBK[] = $addinString;
return false;
}
foreach ($stringBK as $key => $val) {
if ($addinString == $val) {
return true;
}
}
$stringBK[] = $addinString;
return false;
}
for ($i = 0; $i < checkstrlength($string); $i++) {
$count = 0;
for ($j = 0; $j < checkstrlength($string); $j++) {
if ($string[$i] == $string[$j]) {
if (checkString($string[$i], $stringBK)) {
continue 2;
}
$count++;
echo "Column => " . $string[$j] . " for count" .$count . "<br>";
}
}
}
function checkstrlength($string) {
$count = 0;
for ($i = 0; $string[$i] != ""; $i++) {
$count++;
}
return $count;
}
It gives below output ,
Column => s for count1
Column => d for count1
Column => k for count1
I am expecting it as ,
Column => s for count 2
Column => d for count 2
Column => k for count 1
Ok, there a couple of things to look at here.
The checkstrlength() has the below loop.
for ($i = 0; $string[$i] != ""; $i++) {
Formally speaking, we usually look at \0 terminating character in the string to terminate our loop. But in PHP, everything is a string. So, \0 is now a string to match on rather than a character match. Better, we do an isset check to stop our loop. So, code would look like:
for ($i = 0; isset($string[$i]); $i++) {
Second is your not caching the result which you got from checkstrlength(). Do it. Also, you can start the inner loop from $i itself. There is no need to go from start again. So, for loop would look like:
$length = checkstrlength($string);
for ($i = 0; $i < $length; $i++) {
for ($j = $i; $j < $length; $j++) {
Third is that there is no need of empty and count checks in checkString. This also reduces inbuilt function calls. You can simply loop over and return true if found. If not found, we are adding it anyway. So it would look like:
function checkString($addinString, &$stringBK) {
foreach ($stringBK as $key => $val) {
if ($addinString == $val) {
return true;
}
}
$stringBK[] = $addinString;
return false;
}
Now, in your nested loop, you add it to $stringBK outside of the inner loop, because there is no point in checking with the inner loop when chars match. This is because if some character was visited, why initialize the inner loop at all. Just have a check above and continue the search and count. Also note that you are having echo statements inside the inner loop which doesn't make sense because we haven't finished the count yet. Let's do and print it outside of the inner loop at the end. Snippet as follows:
for ($i = 0; $i < $length; $i++) {
$count = 0;
if (checkString($string[$i], $stringBK)) {
continue;
}
for ($j = $i; $j < $length; $j++) {
if ($string[$i] == $string[$j]) {
$count++;
}
}
echo "Column => " . $string[$i] . " for count : " .$count,PHP_EOL;
}
Final Code Demo: https://3v4l.org/4dpST

Sudoku solving/generating algorithm in PHP

I'm having trouble with a specific part of my algorithm and was hoping someone has an idea what I'm doing wrong.
My program basically works like this:
Create 81 empty cells, fill each cell step per step while checking if it's valid there.
I have 3 valid checks and the horizontal valid check (if numbers are double or more in 1 line) is already giving me trouble.
This is my function:
private function isValidHorizontal($index)
{
for ($i = 0; $i < 81; $i += 9){
$firstIndex = $i * 9;
$lastIndex = 9 * ($i + 1) - 1;
// fisrt loop tracking fowards, 2nd loop tracking backwards
if ($index >= $i && $index <= $lastIndex) {
for ($j = 0; $j <= $lastIndex; $j++) {
if ($this->cell[$index]->getValue() == $j) {
return false;
}
}
for ($k = 0; $k >= $firstIndex; $k--){
if ($this->cell[$index]->getValue() == $j) {
return false;
}
}
}
}
return true;
}
$index is the position of the cell so when $index = 0 that would be the very first cell. Last cell would be $index = 80
$this->cell[$index]->getValue() returns an int number i checked so I'm getting the value correctly.
The problem it somehow never returns true
Any Ideas? obviously this is just part of the code, if you need more to help, write a comment and I'll edit :)
In the second inner loop you are using $j instead of $k:
for ($k = 0; $k >= $firstIndex; $k--){
if ($this->cell[$index]->getValue() == $j) { // Here, change to $k
You already got the right answer from #this.lau_, but If I may offer some advice, you could shorten it up a bit by changing the logic. PHP isn't really the best suited language for this, so it'll still look a bit clunky, but I might be worth taking a look at. :)
private function isValidHorizontal($index) {
$taken = [];
foreach (range($index, 81, 9) as $i) {
$value = $this->cell[$i]->getValue();
if (is_int($value) && in_array($value, $taken)) {
return false;
}
$taken[] = $value;
}
return true;
}

PHP List All Combination of Elements of Array

I have an array:
$arr=array("A","B","C");
I want to make its all of combination as:
array("A")
array("B")
array("C")
array("A","B")
array("A","C")
array("B","C")
array("A","B","C")
i want to make an process all of this combinations but i don't want generate all combinations, store them in an array and apply function to them. Because this requires a lot of memory with large combinations. I have 40 items for this process (I have long time but i don't have enough memory).
I want to have a function like this:
function ProcessArrayCombinations($array){
foreach($array as $v){
//generate and process next combination of array
print_r($nextcombination);
}
}
Thank you.
This code recognizes the combinations as binary numbers, using the fact that there is a formula which states that the sum of all combinations possible from n elements is 2^n. Knowing its binary logarithm is integer, we can define a model where each possible binary number constructed from n digits is a set of combinations. Code is untested, if there are typos, please, let me know in comments.
function ProcessArrayCombinations($array) {
$status = array();
foreach ($array as $element) {
$status[] = false;
}
$elementCount = count($status);
$trues = 0;
while ($trues < $elementCount) {
$index = 0;
$stop = false;
while ((!$stop) && ($index < count($status)) && ($status[$index])) {
$status[$index] = false;
$trues--;
$index++;
}
$status[$index] = true;
$trues++;
//Found a new combination
//We should print elements from $array located at indexes fulfilling
//the criteria that the element having the same index in $status is true:
//for ($i = 0; $i < count($status); $i++) {
// if ($status[$i}) {
// print
// } else {
// don't print
// }
//}
}
}
I edited and used your function as below. Thank you again Lajos.
function ProcessArrayCombinations($array) {
$status = array();
foreach ($array as $element) {
$status[] = false;
}
$elementCount = count($status);
$trues = 0;
while ($trues < $elementCount) {
$index = 0;
$stop = false;
while ((!$stop) && ($index < count($status)) && ($status[$index])) {
$status[$index] = false;
$trues--;
$index++;
}
$status[$index] = true;
$trues++;
//Found a new combination
//We should print elements from $array located at indexes fulfilling
//the criteria that the element having the same index in $status is true:
for ($i = 0; $i < count($status); $i++) {
if ($status[$i]) {
echo $array[$i];
}
}
echo '<br/>';
}
}

how do I make an array position equal a variable

what I want to do is run this for loop and within there is a foreach searching the positions. what I want to do is once there it returns false I want it to break and save the position of $i in a variable. I'm using simple_html_dom.php but I don't think that matters since this is more of a basic programming problem.
for($i = $0; $i < $20; $i++){
foreach($html->find('div[class=cate_link]',$i) as $a){
if (strpos($a->plaintext,'+info') == false){
break;
}
}
//this is not valid, but essentialy this is what I want to do.
$stop = $i;
}
To break multiple levels in a loop you simply specify the levels, eg, break 2 - see the manual on break - http://www.php.net/manual/en/control-structures.break.php.
As such your code might work as
for($i = $0; $i < $20; $i++){
foreach($html->find('div[class=cate_link]',$i) as $a){
if (strpos($a->plaintext,'+info') == false){
$stop = $i; // Set variable
break 2; // break both loops
// or alternatively force the outer loop condition to expire
//$i = 21; // Force the outer loop to exit
//break;
}
}
}
I have expanded to question to set $i = 21 to break the outer loop with a single break.
Untested code but syntax checked...
<?php
// Untested code...
// Assume that you WILL break out of the loops...
$currentForIdx = -1; // so we can test that 'for' loop actually ran
$quitLoops = false;
for($i = 0; $i < $20 && !quitLoops; $i++) {
$currentForIdx = $i; // in case we break out of the loops
foreach($html->find('div[class=cate_link]',$i) as $a){
if (strpos($a->plaintext,'+info') == false) {
$quitLoops = true;
break;
}
}
}
// test $quitLoops and $currentForIdx to work out what happened...
?>
I havent tested this, but I would try something like this:
for($i = $0; $i < $20; $i++){
$stop = false;
foreach($html->find('div[class=cate_link]',$i) as $a){
if (strpos($a->plaintext,'+info') == false){
$stop = $i;
}
}
if ($stop !== false) {break;}
}

Getting an undefined offset in my PHP array while in a foreach

I need some help, even though I think I'm checking for the length of the array and I should be breaking out of the loop, I still get warnings on my [else if ($value....] line. So either I'm missing something crucial or I've been staring at this code segment too long and its obvious. Any insight would be appreciated.
$count = count($filter); //Filter is an array
if ($count > 1 ){
//Compare values and generate a range to choose from
$i = 1;
foreach($filter as $value){
//Break the loop if at the end of the array
if ($i >= $count){
//throw new exception($i .' '.$count);
break;
}
//if the value is smaller then the next procceding value, because they are already in order of presidence,
//add it to our range of potentials.
else if($value < $filter[$i]->value){
array_push($range, key($filter));
}
$i++;
}
}else {
return false;
}
I suspect that there are gaps in your array. Try this:
$filter = array_values($filter); // this will remove any gaps in the array
$count = count($filter);
if ($count <= 1)
return false;
for ($i = 0; $i < $count; $i++)
{
if ($i != $count-1 && $filter[$i]->value < $filter[$i+1]->value)
array_push($range, key($filter));
}
Your array might have non-numeric keys. Then try this:
foreach($filter as $key=>$value)
{
// test for $filter[$key];
}
Or your $filter array doesn't hold objects, then you can't use the -> in
$filter[$key]->value
try this code.... no need of checking count..
$range = array();
$i = 1;
foreach($filter as $value)
{
if(isset($filter[$i]) && $value < $filter[$i]->value)
{
array_push($range, key($filter));
$i++;
}
else
{
break;
}
}

Categories