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PHP array subscripts can start from 0
In PHP, arrays are a very common data structure used to store and manage a set of data. Through arrays, we can store multiple variables in a container and access and operate them in specific ways. In PHP, array elements are accessed through subscripts, and array subscripts start from 0.
Why do PHP array subscripts start from 0?
PHP array subscripts start from 0, and the history of this design can be traced back to the C language. C language is a commonly used programming language and the main programming language of the Unix operating system. In C language, array subscripts also start from 0. Therefore, this tradition continues in PHP as well.
Benefits of PHP array subscripts starting from 0
Although some developers may feel that subscripts starting from 0 will cause inconvenience when using them, in fact, PHP arrays start from 0 The subscript design has many benefits:
The subscript method starting with 0 can make the program code clearer and more intuitive, and the code volume is also larger compact. In this way, we can access the array elements more conveniently, thus improving the readability and maintainability of the code.
Since many programming languages support array subscripts starting from 0, such as C, Java, etc., PHP starts from 0 The array subscript design can make the interaction between PHP and these programming languages more convenient.
If the array subscript starts from 1, then when the array length is N, N 1 memory space needs to be allocated to store all elements. And if the array index starts from 0, then only N memory spaces need to be allocated to store all elements. This memory savings can make a huge difference when storing large amounts of data.
The impact of PHP array subscripts starting from 0
If you come from other programming backgrounds, you may find it inconvenient that PHP array subscripts start from 0. In actual development, we need to adapt to the design that PHP array subscripts start from 0.
In PHP, if you want to access the first element in the array, you need to use $array[0] instead of $ array[1]. If you want to access the last element in the array, you need to use $array[count($array)-1] instead of $array[count($array)].
In a loop structure, if you want to traverse an array, you can use a for loop or a foreach loop. For a for loop, you usually need to start with $i=0 and set the loop condition in the manner of $i < count($array). For a foreach loop, you need to use as $key => $value to traverse the array.
Summary
In PHP, array subscripts starting from 0 is a very common design method. Although some developers may find it uncomfortable, in actual development, we need to adapt to this design solution. At the same time, we also need to realize that the array subscript design starting from 0 has the benefits of being convenient, intuitive, easy to interact with other programming languages, and saving memory.
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