An array of PHP learning

This article to share the content of PHP in the knowledge of the array, the need for friends can refer to

Array what's not very simple
int a[1100000]
But that's not what PHP is.

<?php    $n =1;    $a =array (array ());    $s =array ();    $s [1]= "S30408";    $a [1][1][1]=0; $a [1][1][2]=1.05;    $a [1][2][1]=0; $a [1][2][2]=2.04;    $a [1][3][1]=7.90; $a [1][3][2]=11.15;    $a [1][4][1]=17.80; $a [1][4][2]=20.20;    $a [1][5][1]=0; $a [1][5][2]=0.09;    $a [1][6][1]=0; $a [1][6][2]=0.055;    $a [1][7][1]=0; $a [1][7][2]=0.035;? >

This is a three-dimensional array, isn't it some trouble?
Let's talk about one-dimensional arrays.

<?php    $s =array ();/* Each array is a dimension */    $s [1]=100; $s [2]=200;    Echo $s [1]+ $s [2];? >

This is the array. I have a full array of PHP

<?php    $v =array ();    $a =array ();    function Dfs ($k) {        Global $v, $a, $n;        if ($k = = $n + 1) {for            ($i =1; $i <n; $i + +) {                echo $v [$i], "";            }            echo $v [$n], "<br>";        }        else{for            ($i =1; $i <=n; $i + +) {                if ($v [$i]==true) {                    $v [$i]=false;                    $a [$k]= $i;                    DFS ($k + 1);                    $v [$i]=true;    }}} DFS (5);? >

This is the full array of 5.
It seems a bit wrong, but not afraid.
Just look at the examples.
The two-dimensional connection is simple.
It is

$s =array (array ());

That's it.
What about tomorrow's chapter?
Let's talk about some arithmetic loops.

Array what's not very simple
int a[1100000]
But that's not what PHP is.

<?php    $n =1;    $a =array (array ());    $s =array ();    $s [1]= "S30408";    $a [1][1][1]=0; $a [1][1][2]=1.05;    $a [1][2][1]=0; $a [1][2][2]=2.04;    $a [1][3][1]=7.90; $a [1][3][2]=11.15;    $a [1][4][1]=17.80; $a [1][4][2]=20.20;    $a [1][5][1]=0; $a [1][5][2]=0.09;    $a [1][6][1]=0; $a [1][6][2]=0.055;    $a [1][7][1]=0; $a [1][7][2]=0.035;? >

This is a three-dimensional array, isn't it some trouble?
Let's talk about one-dimensional arrays.

<?php    $s =array ();/* Each array is a dimension */    $s [1]=100; $s [2]=200;    Echo $s [1]+ $s [2];? >

This is the array. I have a full array of PHP

<?php    $v =array ();    $a =array ();    function Dfs ($k) {        Global $v, $a, $n;        if ($k = = $n + 1) {for            ($i =1; $i <n; $i + +) {                echo $v [$i], "";            }            echo $v [$n], "<br>";        }        else{for            ($i =1; $i <=n; $i + +) {                if ($v [$i]==true) {                    $v [$i]=false;                    $a [$k]= $i;                    DFS ($k + 1);                    $v [$i]=true;    }}} DFS (5);? >

This is the full array of 5.
It seems a bit wrong, but not afraid.
Just look at the examples.
The two-dimensional connection is simple.
It is

$s =array (array ());

That's it.
What about tomorrow's chapter?
Let's talk about some arithmetic loops.