for循环中未定义的偏移量错误

Question

This code helps me find the minimum of certain sums, so I set a function as the one below:

 function GetMin($s)
    {

        for($j=1;$j<=count($s)-1;$j++)
        {
            $min=$s[1];
            if($s[$j] < $s[$j+1] && $s[$j] < $min)
            {
                $min=$s[$j];
            }
    else {continue;}        
        }
        echo $min;
    }

$enc=".129.25.24.154.546.214.142.254.256";
$ar=explode(".",$enc);
for($i=0;$i<count($ar)-1;$i+=3)
{
    $s[$i+1]=$ar[$i+1]+$ar[$i+2]+$ar[$i+3];
    echo $s[$i+1]."<br>";
}


GetMin($s)

The code should work this way:

Calculates the sum of every 3 terms of the array and store it in a term of another array called "s", the code is working well, until I try to find the minimum, it prints the minimum but with the error below:

Notice: Undefined offset: 2 in C:\\Program Files (x86)\\Apache Software Foundation\\Apache2.2\\htdocs\\decrypt.php on line 9 Notice: Undefined offset: 2 in C:\\Program Files (x86)\\Apache Software Foundation\\Apache2.2\\htdocs\\decrypt.php on line 9 Notice: Undefined offset: 3 in C:\\Program Files (x86)\\Apache Software Foundation\\Apache2.2\\htdocs\\decrypt.php on line 9 178

Answer 1

It looks like you're trying to get the lowest value in an array of values, so I've changed your GetMin() function to work with the non-consecutively indexed array that you create prior to calling GetMin() . This should work for you:

<?php
function GetMin($s){
    $min = NULL;
    foreach($s as $v){
        if(is_null($min)){
            $min = $v;
        } elseif($v < $min){
            $min = $v;
        }
    }
    return $min;
}
$enc = ".129.25.24.154.546.214.142.254.256";
$ar = explode(".",$enc);
$ar_count = count($ar);
for($i=0;$i<$ar_count-1;$i+=3)
{
    $s[$i+1]=$ar[$i+1]+$ar[$i+2]+$ar[$i+3];
    echo $s[$i+1]."<br>";
}


echo GetMin($s);