Undefined offset error in for loop - php

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);