This article will share with you the knowledge of arrays in PHP. Friends in need can refer to it
Arrays are not very simple
int a[1100000]
But PHP is not like this
<?php $n=1; $a=array(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, is it a little troublesome?
Let’s start with one-dimensional arrays.
<?php $s=array();/*每一个array就是一个维度*/ $s[1]=100;$s[2]=200; echo $s[1]+$s[2];?>
This is an array. I have a full arrangement 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 to find the full arrangement of 5.
It seems a little wrong, but don’t be afraid.
Just look at the example
Just connect the two-dimensional one to the very simple one
That’s it
$s=array(array());
That’s it
I will update a chapter tomorrow, what will I talk about?
Let’s talk about some operation loops.
Isn’t an array very simple?
int a[1100000]
But php is not like this
<?php $n=1; $a=array(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, is it a little troublesome?
Let’s start with one-dimensional arrays.
<?php $s=array();/*每一个array就是一个维度*/ $s[1]=100;$s[2]=200; echo $s[1]+$s[2];?>
This is an array. I have a full arrangement 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 to find the full arrangement of 5.
It seems a little wrong, but don’t be afraid.
Just look at the example
Just connect the two-dimensional one to the very simple one
That’s it
$s=array(array());
That’s it
I will update a chapter tomorrow, what will I talk about?
Let’s talk about some operation loops.
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PHP learning for the first time learning PHP
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