Why is the output empty?

[Anne693]

#include <iostream>
#include <cctype>
#include <cstring>
using namespace std;
void mycode(char msg[ ],char ch)
{
        for (int cnt=0;msg[cnt]='\0';cnt++)
        {
            if ((msg[cnt]>='B')&&(msg[cnt]<='G'))
                msg[cnt]=tolower(msg[cnt]);
            else if ((msg[cnt]=='A')||(msg[cnt]=='a'))
                msg[cnt]=ch;
            else if ((cnt%2)==0)
                msg[cnt]=toupper(msg[cnt]);
            else
                msg[cnt]=msg[cnt-1];
        }
}
int main()
{
    char mytext[20]="ApEACeDriVE";
    mycode(mytext, '@');
    cout<<"NEW TEXT: "<<mytext<<"\n";
    return 0;
}

The output I'm getting is:

NEW TEXT:         

[Thomas1965]

Line 7 look dubious. Didi you mean != '\0' ?

[Anne693]

Thank you so much!