[C++]Eliminati cifrele cuprinse intre c1 si c2

//Se da un nr n. Sa se elimine toate cifrele cuprinse intre c1 si c2(c1<c2).
#include <iostream.h>
#include <fstream.h>

int c1, c2, x;
long n;

void citire()
{
    ifstream f("cit.in");
    f>>n;
    f>>c1>>c2;
}

void numar(long n, int c1, int c2, int x)
{
    int og=0, c=0;
    while(n)
    {
        c=n%10;
        if(c >= c1 && c <= c2)
        {
        }
        else
        {
            x=x*10+c;
        }
        n/=10;
    }
    while(x)
    {
        og=og*10+x%10;
        x/=10;
    }
    cout<<og;
}

int main()
{
    citire();
    numar(n, c1, c2, x);
}
/* cit.in */
162448
4 7

/*
Ex: n=162448, c1=4, c2=7;
Valoarea furnizata este 128
*/