Format
#include <stdlib.h> void srand(unsigned int seed);
Language Level: ANSI
Threadsafe: No.
Description
The srand() function sets the starting point for producing a series of pseudo-random integers. If srand() is not called, the rand() seed is set as if srand(1) were called at program start. Any other value for seed sets the generator to a different starting point.
The rand() function generates the pseudo-random numbers.
Return Value
There is no return value.
Example that uses srand()
This example first calls srand() with a value other than 1 to initiate the random value sequence. Then the program computes five random values for the array of integers that are called ranvals.
#include <stdlib.h> #include <stdio.h> int main(void) { int i, ranvals[5]; srand(17); for (i = 0; i < 5; i++) { ranvals[i] = rand(); printf("Iteration %d ranvals [%d] = %d\n", i+1, i, ranvals[i]); } } /****************** Output should be similar to: **************** Iteration 1 ranvals [0] = 24107 Iteration 2 ranvals [1] = 16552 Iteration 3 ranvals [2] = 12125 Iteration 4 ranvals [3] = 9427 Iteration 5 ranvals [4] = 13152 */
Related Information
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