How can I hide a flag from `strings` command

I want to create RE CTF, that the user needs to discover which string he need to write in order to execute a function that will print the flag, but, with a simple strings command in shell, we can discover the flag in the printf function. So, how can we make this not to happen?

#include <stdio.h>  void print_flag() {     printf("secret_string discovered. flag: {eAsy_p3asy}"); }  int main() {     int c;     c = getchar();     while (c != 'secret_string') {         putchar(c);         c = getchar();     }     print_flag();     return 0; } 

strings output: I include only the flag. I don’t want the flag to be visible like this, it makes no sense.

secret_string discovered. flag: {eAsy_p3asy}