delete[] array caused a breakpoint - c++

Question

I am trying to move a part of my code from main function to the additional void function, but I keep getting a problem with deleting allocated memory in the end. By that moment my program did not printed out my array as it should have. So i am looking for a tip how i can fix this.
#include "pch.h"
#include <iostream>
using namespace std;
void push(char* C, int size, istream &in);
void print_str(char* word, int length);
int main()
{
char* C = new char[0];
int size = 0;
cout << "input your text: ";
push(C, size, cin);
print_str(C, size);
delete[] C;
return 0;
};
void print_str(char* word, int length) {
for (int k = 0; k < length; k++)
{
cout << word[k];
}
cout << " ";
};
void push(char* C, int size, istream& in) {
while (1) {
char current = in.get();
if (current == '\n')
break;
else {
char* text1 = new char[size];
for (int i = 0; i < size; i++)
text1[i] = C[i];
delete[] C;
C = new char[size + 1];
for (int i = 0; i < size; i++)
C[i + 1] = text1[i];
delete[] text1;
C[0] = current;
}
size++;
}
}
Breakpoint

Answer 1

push changes the value of C, so it must return the new value so that the other code can see the change. Like this (for instance)
int main() {
...
C = push(C, size, cin);
...
}
char* push(char* C, int size, istream& in) {
while (1) {
char current = in.get();
if (current == '\n')
break;
else {
char* text1 = new char[size];
for (int i = 0; i < size; i++)
text1[i] = C[i];
delete[] C;
C = new char[size + 1];
for (int i = 0; i < size; i++)
C[i + 1] = text1[i];
delete[] text1;
C[0] = current;
}
size++;
}
return C;
}

Answer 2

you need to define c as pointer to pointer , because changing c in push scope won't change value of c in main
here's the changed code
#include "pch.h"
#include <iostream>
using namespace std;
void push(char** C, int size, istream& in);
void print_str(char* word, int length);
int main()
{
char* C = new char[0];
int size = 0;
cout << "input your text: ";
push(&C, size, cin);
print_str(C, size);
delete[] C;
return 0;
};
void print_str(char* word, int length) {
for (int k = 0; k < length; k++)
{
cout << word[k];
}
cout << " ";
};
void push(char** C, int size, istream& in) {
while (1) {
char current = in.get();
if (current == '\n')
break;
else {
char* text1 = new char[size];
for (int i = 0; i < size; i++)
text1[i] = (*C)[i];
delete[] C;
*C = new char[size + 1];
for (int i = 0; i < size; i++)
C[i + 1] = text1[i];
delete[] text1;
(*C)[0] = current;
}
size++;
}
}
also you can make more efficient algorithms to reach your end ,instead of allocating and deallocating memory for each character witch is costy