hi i just made a program to practice random numbers because im new. i get different numbers each time, but every time i run the program they are the same numbers each time. anyone know the problem? thanks in advance.
Code:#include<stdio.h> #include<stdlib.h> int number(void); main() { number(); number(); number(); printf("hit a key to quit"); getchar(); return 0; } int number(){ int fy=1,fz=100,fx; fx=rand() % (fz-fy+1); printf("Your number is %d\n",fx); return fx; }
What you are talking about is not random numbers, they are pseudo-random numbers. A pseudo-random generator such as the standard C library function rand( ) uses a start seed and from that start seed there will be a mathematically defined sequence of pseudo-random numbers returned each time it is called. To get a new sequence each time you run your program you need to set a different seed with srand( ). This can be accomplished by using the current time like this:
Code:#include <stdlib.h> #include <stdio.h> #include <time.h> int main( ) { int n; srand( time( 0 ) ); /* Generate a new seed */ for ( n = 0; n < 100; ++n ) printf( "%i, ", rand( ) ); return 0; }
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http://eternallyconfuzzled.com/articles/rand.html
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Last edited by dwks; 11-24-2005 at 09:00 AM.
dwk
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