Always the same output with rand() with different ide envirionment too

why does it always give the same output even tho i run it again or run it on a different ide

#include <stdio.h>
#include <stdlib.h>
int numbers[100];
void rastnumaraekle(int insert){
    numbers[insert]=rand()%1000;
}

int main(void){
    rastnumaraekle(0);
    rastnumaraekle(1);
    rastnumaraekle(2);
    printf("%d\n",numbers[0]);
    printf("%d\n",numbers[1]);
    printf("%d\n",numbers[2]);
}