Shifting every element in C++ array to the left - c++

Question

I'm trying to write a function delete an element in a C++ array, that is, shift every element one to the left, starting at the index.
The code
#include <iostream>
using namespace std;
const int MAX_SIZE = 50;
void fill_array(char array[], int &current_size, const int max_size);
void print_array(const char array[], const int current_size);
int delete_index(char array[], int &current_size, int index);
int main () {
char array[MAX_SIZE] = {' '};
int current_size = 0;
fill_array(array, current_size, MAX_SIZE);
int index = 4;
delete_index(array, current_size, index);
cout << "After deleting element at index " << index << " the array is: ";
print_array(array, current_size);
return 0;
}
int delete_index(char array[], int &current_size, int index) {
// Check input
if (index > current_size) {
cout << "Index must be between 0 and " << current_size - 1 << endl;
return -1;
}
for (int i = index; i < current_size; i++) {
cout << "array[" << index << "] = " << index << endl;
array[index] = array[index + 1];
}
current_size--;
cout << current_size << endl;
return 0;
}
However, the output I get when inputting "thisisnotworking" and index 4 is:
Please input characters for the array (max of 50) or enter '*' to quit:
onetwothree*
array[4] = 4
array[4] = 4
array[4] = 4
array[4] = 4
array[4] = 4
array[4] = 4
array[4] = 4
10
After deleting element at index 4 the array is: onetoothre
I don't understand it is not increasing the index in the for loop.
I've read similar questions here and elsewhere but couldn't fix the problem still. Any idea why this is?
NOTE: I only want to use arrays (not vectors, etc.).

Answer 1

for (int i = index; i < current_size; i++) {
cout << "array[" << index << "] = " << index << endl;
array[index] = array[index + 1];
}
Your loop counter is i. Inside your loop, you should use i instead of index
Corrected:
for (int i = index; i < current_size; i++) {
cout << "array[" << i << "] = " << array[i] << endl;
array[i] = array[i + 1];
}

Answer 2

Because you use array[index] = array[index + 1] while you need array[i] = array[i + 1]
It's the same here: cout << "array[" << i << "] = " << i << endl;

Answer 3

use pointers to dynamically change the size:
#include <iostream>
using std::cout;
using std::cin;
using std::endl;
int* ClearElement(int array[], int index, const int& SizeOrig, int& NewSize)
{
array[index] = -1;
NewSize = SizeOrig;
NewSize--;
int* ptrArray = new int[NewSize];
if(!ptrArray)
throw "No more memory!";
for(int i(0), j(0); i < SizeOrig; i++)
{
if(-1 != array[i])
{
ptrArray[j] = array[i];
j++;
}
}
return ptrArray;
}
int main()
{
int array[] = {1, 2, 3, 4, 5, 6, 7, 8, 9, 10};
int SizeOrig = (sizeof(array) / sizeof(int));
int NewSize = SizeOrig;
int index;
try{
cout << "element index to clear: ";
cin >> index;
cout << endl;
if(index < 0 || index > NewSize)
throw "out of boundary index!";
int* ptrArray = ClearElement(array, index, SizeOrig, NewSize);
for(int i(0); i < NewSize; i++)
cout << ptrArray[i] << ", ";
delete[] ptrArray;
}
catch(char* cp)
{
cout << cp << endl;
exit(1);
}
catch(...)
{
cout << "sorry an error has happened!";
exit(1);
}
cout << endl << endl << endl;
return 0;
}

Answer 4

You can also use std::copy from algorithm
int max = 10;
int array[] = {1, 2, 3, 4, 5, 6, 7, 8, 9, 10};
int index = 4;
std::copy(array+index+1, array+max, array+index);