#include <iostream>
using namespace std;
 
int main() {
 
bool open_bracket = true;
bool end = false;
 
size_t pos_open = 0;
size_t pos_close = 0;
 
const char *dvar_hostname = "123[456]79[88]";
string dh(dvar_hostname);//get string value
while(!end){
	pos_open = dh.find('[');
	pos_close = dh.find(']');
 
 
	if(pos_open == string::npos || pos_close == string::npos || pos_close < pos_open){
		end = true;
	}else{
		dh.erase(pos_open, pos_close - pos_open + 1);
	}
	cout << pos_open <<endl;
	cout << pos_close <<endl;
	cout << dh <<endl;
}
 
dvar_hostname = dh.c_str();//convert back
cout << dvar_hostname;
	return 0;
}

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