constexpr3.cc

#include "stdio.h"

#define KEY 0x55

template <unsigned int N>
struct obfuscator {
  
    char m_data[N] = {0};
    constexpr obfuscator(const char* data) {/*...*/};

    /*
     * deobfoscate decrypts the strings. Implement decryption algorithm here.
     * Here we have a simple XOR algorithm.
     */
    void deobfoscate(unsigned char * des) const{
        int i = 0;
        do {
            des[i] = m_data[i] ^ KEY;
            i++;
        } while (des[i-1]);
    }

};

int main() {
    // Store "Hello" in obfuscated form using simple xor encryption.
    constexpr auto obfuscated_str = obfuscator<6>("Hello");
    // Create a buffed to store decrypted string.
    unsigned char buff[0x10] = {0};
    // Decrypt the string
    obfuscated_str.deobfoscate(buff);
    printf("%s", buff); // output: Hello
    return 0;
}