How to use rand() function in php

The rand() function in PHP is used to generate random integers ranging from 0 to RAND_MAX (default 2147483647). You can specify the minimum and maximum values ​​as parameters, and the function returns a random integer between the two values.

Usage of rand() function in PHP

rand() function is a built-in function for Generate random numbers. It generates a random integer ranging from 0 to RAND_MAX, which is a constant and defaults to 2147483647.

Syntax:

int rand([int $min [, int $max]])

Parameters:

• $min: (optional ) specifies the minimum value of the random number, the default is 0.
• $max: (optional) Specifies the maximum value of the random number, the default is RAND_MAX.

Return value:

The function returns a random integer between $min and $max (inclusive of bounds).

Example:

// 生成一个随机数（0-2147483647）
$num = rand();

// 生成一个随机数（10-100）
$num = rand(10, 100);

Note:

• rand() function can only generate pseudo-random numbers. The randomness on depends on the input (seed).
• If the rand() function is called multiple times in the same script, predictable random numbers will be generated. To get truly random numbers, you need to use the mt_rand() or random_int() function.

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