char* array of pointers modification [closed] - arrays

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I am new to c language after learning python and java and I encountered an interesting exercise that i cannot find answer online for.
Given an *char array of pointers to string (*char arr[N(N is defined)]={"sadsd","gasgs"......})
what is the proper way to pass given array of string pointers to a function so that the function will be able to modify the array?
For example if i want to print the array with a different position for each element in it? After i pass the array pointer to the function I cant modify the array for some reason without using [] do define the elements I want to work on. the exercise is to use pointer arithmetics without using [].
thank you and have a great day :)

Answer 1

Passing an array of strings to a function can be done with a declaration like this :
void function(char ** strArray);
The size cannot be found from such a pointer so it should be passed too :
void function(char ** strArray, int arraySize);
Indices are accessible with [] from 0 to arraySize-1. Pointer arithmetic allow doing the same with a different syntax :
strArray[5] // Gives a string (whose the size could then be found with strlen)
*(strArray + 5) // Equivalent form using pointer arithmetic
Here is an example printing the array content after having changed the second index :
void printStringArrayContent(char ** array, int size) {
*(array + 1) = "Margaret";
for(int i=0; i<size; i++) {
printf("%s ", *(array + i));
}
printf("\n");
}
void main(){
char * array[3] = { "John", "Sarah", "Michael" };
printStringArrayContent(array, 3); //==> John Margaret Michael
}