c - Setting an Array of Integer Pointers -

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i trying set array of integer pointers. programs supposed set pointers @ index point integer of value 2*i. programs should print out pointees of first 5 pointer elements, should 0,2,4,6,8.

for reason getting segmentation fault. tell me why happens , can fix it?

i attempted replace final line " arr[index] = &i; ", not give me segmentation fault still gives me wrong results.

help appreciated, starting off array of pointers. 

#include <stdio.h>  void setarr (int);  int * arr[10]; // array of 10 int pointers  int main(int argc, char *argv[]) {     int i;          setarr(0);         setarr(1);         setarr(2);         setarr(3);         setarr(4);           for(i=0; i<5;i++)            printf("arr [%d] = %d\n", i, *arr[i]);  /* should 0, 2, 4, 6, 8 */      return 0; }  /* set arr[index], pointer, point integer of value 2*index */ void setarr (int index){   int = 2 * index;   * arr[index] = i; }

the problem not allocating memory each item in array points to. line

*arr[index] = i;

will set random memory address (whatever in arr[index]) value of i.

what should is:

void setarr(int index) {     int *i = malloc(sizeof(int)); // allocate memory value     *i = 2 * index; // set value     arr[index] = i; // make array slot point @ value }

but need make sure free() memory later. example, before return 0; statement in main() function, put:

for (i = 0; < 5; i++)     free(arr[i]);

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