PHP learning array-PHP Tutorial-php.cn

PHP learning array

不言

Release： 2023-03-23 11:20:02

Original

1869 people have browsed it

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;?>

Copy after login

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];?>

Copy after login

PHP learning array
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);?>

Copy after login

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());

Copy after login

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;?>

Copy after login

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];?>

Copy after login

PHP learning array
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);?>

Copy after login

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