By running this code
for ( i = 0; i < 6; ++i )
printf("%i ", array[i]);
64 0 -64 77 67 0
No. There's no such thing guaranteed by the C standard for local variables.
The values of the uninitialized array has indeterminate values. So, you can't access them and since you do, your code has undefined behaviour.
But the variables with static storage duration such as global variables,
static qualified variables etc are initialized with zero.