Remove an Array element [closed] - objective-c

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So im trying to code a function to remove an element from an Array.for some reason i'm getting no errors but still does not print the result i need. i think the problem is in the function or data type declaration.
#import <Foundation/Foundation.h>
void deleteArray(char stra[ ], char ElementToRemove);
int main(int argc, const char * argv[]) {
#autoreleasepool {
char str[100];
printf("Please Enter Array Elements\n");
scanf("%s",&str);
deleteArray(str, "a");
printf("%s",&str);
}
return 0;
}
void deleteArray(char stra[ ], char ElementToRemove)
{
int NumberOfElements = sizeof(stra);
int ElementPos;
for (int i = 0; i >= NumberOfElements;i++)
{
if (ElementToRemove == stra [i])
{
ElementPos = i;
}
}
for (int SecondCounter = ElementPos; SecondCounter >= NumberOfElements;SecondCounter++ )
{
stra[SecondCounter] = stra[SecondCounter - 1];
}
}

Answer 1

There are many issues with your code, let's see them one by one.
When you pass an array to a function, it decays to a pointer to the first element of the array. So, sizeof in the deleteArray() function is not doing what you think it's doing there.
You can use strlen() instead to get the length of a char array. However, please note, this does not count the terminating null, anyways, and you need to move that one, too, to make the end of the modified array.
Then, in the for loop,
for (int i = 0; i >= NumberOfElements;i++) //false always....
is wrong. I believe what you want is
for (int i = 0; i < NumberOfElements;i++)
After that, regarding the call to the function should be
deleteArray(str, 'a'); // 'a' is a char
instead of
deleteArray(str, "a"); // "a" denotes a string
Next, in the main() function, remove the & from the argument to printf(). It should look like
printf("%s",str);
Also, to ensure safety from buffer overflow, you should make yourscanf() to look like
scanf("%99s",str);

Answer 2

If you need dynamically sized arrays, I recommend making them the last flexible array member (that wikipage has an example) of some (growable) struct and keep the size of that array in its containing struct ....

Answer 3

If you want to have array features, such as add, delete, move and so on, use linked lists. Linked lists are using pointers, so you can represent an array using them. This way it is possible to delete an element, move it or add a new one.
When declaring an array in c, you declare it fixed size. In your case, if you want not to use pointers and lists, you have to copy array elements to a new one, excluding the unneeded.