所有可能的子串PHP

所有可能的子串PHP

问题描述:

I use this function to get all the possible substrings of the $input="KRKRK". iT gives out some of the substrings , but doesn't take into consideration the first word of the string(i.e, K) into consideration while building up the substrings. What may be the problem?

function get_all_substrings($input)
{
  $input = trim($input);
  $subs = array();
  $length = strlen($input);
  for($i=1; $i<=$length; $i++)
 {
  $start = 0;
  $sub_length = $i;

  while(($start+$sub_length) <= $length)
  {
    $subs[] = substr($input, $start, $sub_length);
    $start++;
  }

 }
 return $subs;
}

Here's the Output array:

Array ( [0] => R [1] => K [2] => R [3] => K [4] => RK [5] => KR [6] => RK [7] => RKR [8] => KRK [9] => RKRK ) 

But why am I not getting the substrings K, KR, KRK, KRKR ??

我使用此函数获取$ input =“KRKRK”的所有可能子串。 iT发出 一些子串,但在构建子串时不考虑字符串的第一个字(即K)。 可能是什么问题? p>

  function get_all_substrings($ input)
 {
 $ input = trim($ input); 
 $ subs = array(); \  n $ length = strlen($ input); 
 for($ i = 1; $ i&lt; = $ length; $ i ++)
 {
 $ start = 0; 
 $ sub_length = $ i; 
 \  n while(($ start + $ sub_length)&lt; = $ length)
 {
 $ subs [] = substr($ input,$ start,$ sub_length); 
 $ start ++; 
} 
 
}  
返回$ subs; 
} 
  code>  pre> 
 
 

这是输出数组: p>

 数组([0]  =&gt; R [1] =&gt; K [2] =&gt; R [3] =&gt; K [4] =&gt; RK [5] =&gt; KR [6] =&gt; RK [7] =  &gt; RKR [8] =&gt; KRK [9] =&gt; RKRK)
  code>  pre> 
 
 

但为什么我没有得到子串K,KR,KRK,KRKR ?? p> div>

Here is what I whipped up -

function get_all_subs($input) {
    $arr = str_split($input);
    $all_subs = array();
    for ($i = 0; $i < count($arr); $i++) {
        for ($j = $i; $j < count($arr); $j++) {
            $all_subs[] = implode('', array_slice($arr, $i, $j - $i + 1));
        }       
    }
    return $all_subs;
}

$input="KRKRK";
$substrings = get_all_subs($input);
print_r($substrings);

Here is a working example.

I honestly had no issues using the script when I ran it...

<?php

function get_all_substrings($input)
{
    $input = trim($input);
    $subs = array();
    $length = strlen($input);
    for($i=1; $i<=$length; $i++)
    {
        $start = 0;
        $sub_length = $i;
        while(($start+$sub_length) <= $length)
        {
            $subs[] = substr($input, $start, $sub_length);
            $start++;
        }
    }
    return $subs;
}

print_r(get_all_substrings("KRKRK"));

?>

This gave me the result:

Array ( [0] => K [1] => R [2] => K [3] => R [4] => K [5] => KR [6] => RK [7] => KR [8] => RK [9] => KRK [10] => RKR [11] => KRK [12] => KRKR [13] => RKRK [14] => KRKRK )

Try this! it will give the result as Array ( [0] => K [1] => KR [2] => KRK [3] => KRKR [4] => KRKRK )

$input="KRKRK";
function get_all_substrings($input)
{
    for($i=0; $i<strlen($input); $i++){
        $individual_char[] = $input[$i];
    }
    $temp_char = "";
    for($i=0; $i<count($individual_char); $i++){
        $final_array[] = $temp_char.$individual_char[$i];
        $temp_char = $temp_char.$individual_char[$i];
    }
    return $final_array;
}
print_r(get_all_substrings($input));