C array setting of array element value beyond size of array

Question

I Have this C code snippet

int numbers[4]={1};

numbers[0]=1; numbers[1]=2; numbers[3]=3; numbers[10]=4;
printf(\"numbers: %d %d %d %d %d %d\\n\",numbers[0],         


        

Answer 1

1. This won't give an error, your array is declared on the stack so what number[10] does is write at the adress number + (10*sizeof int) and overwrites anything that would be there.
2. As Xymostech said 0 can be as much garbage as 963180397. Printing numbers[6] will print what is stored at the address numbers + (6*sizeof int) so it depends on how your program is compiled, if you have declared local variables before of after numbers, etc.
3. See answer 1.

What you can do is this :

int empty[100];
int numbers[4]={1};
int empty2[100];

memset(empty, 0xCC, sizeof empty);
memset(empty2, 0xDD, sizeof empty2);

numbers[0]=1;numbers[1]=2;numbers[3]=3;numbers[10]=4;
printf("numbers: %d %d %d %d %d %d\n",numbers[0],numbers[1],numbers[3],numbers[6],numbers[10],  numbers[5]) ;

Now you can understand what you are overwriting when accessing out of your numbers array