C language generates random numbers

Rand () function

#include <stdlib.h>int rand(void);

Rand () is a function that calculates a series of numbers based on a seed, with a particular algorithm. The number returned is between 0 and Rand_max. Rand_max is defined in stdlib.h, at least 32767.

However, this generates pseudo-random numbers because the seeds are set up after the computer is turned on, so this series of numbers are predictable and each time the sequence is equal. To get a real random number, you have to reset the seed.

Srand () function

#include <stdlib.h>void srand(unsigned int seed);

Srand (seed) is a function of the C language that sets the seed of a random number, usually using time as seed, and each time it runs differently, so the resulting random number seed is also different. Srand (Time (NULL))

How to generate random numbers

1. Call Srand (Time (NULL)), set the random number seed
2. Call Rand () repeatedly to generate a random number

#include <stdlib.h>#include <stdio.h>#include <time.h>            void main( void ){  int i;  srand((unsigned)time(NULL));              for(i = 0; i < 10; i++) {                                  printf("%d\n", rand());    }}

C language generates random numbers