First off, let it be known that I'm relatively new to programming and VERY new to C/C++. Now that that's over...

I have a problem with a simple command line program that is meant to collect a few user inputs and then put them into a shell command with flags. The program then puts those values together to form a command like: program.exe -a value -b value -c value.

The problem is that I can't find a way to use strings in a system() line(the compiler asks for a const char because it can't use a string for System()). I've searched the forum for a while and haven't seen anything to help me(though it seems that the soulution is always right in front of my eyes whenever I ask for help), so sorry if this has already been answered somewhere else.

Here is what I've got so far:
Code:
#include <cstdlib>
#include <iostream>

using namespace std;

int main(int argc, char *argv[])
{
    char inone[21];
    char intwo[21];
    char inthree[21];
    char app[21];
    string space( " " );
        
    cout<< "What is the name of the executable?: ";
    cin.getline ( app, 21 );                     //name of file to run, assuming it's in 'system32'
    cout<< "What is flag one?: ";
    cin.getline ( inone, 21 );                   //flag, along with a value. eg: "-b 1024"
    cout<< "What is flag two?: ";
    cin.getline ( intwo, 21 );
    cout<< "What is flag three?: ";
    cin.getline ( inthree, 21 );
    cout<< "Your command will be: " << ( app ) << ( space ) << ( inone ) << ( space ) << ( intwo ) << ( space ) << ( inthree ) << "... Continue?";
    cin.get();
    /*here is where I want to put a system() line or something similar.
    the problem is that I can't figure out how to combine the flags and app
    name into a string and put it into that system() line.*/
}
In the end, I want to be able to incorporate this into a larger application that will serve as a "frontend" for people new to terminal-based applications(or just lazy people like myself).