/* PBXA64 handbook-style C text example: hex_encoder.
 * encode bytes into hexadecimal nibbles. This source deliberately keeps every transformation visible
 * instead of hiding it behind library calls, making it useful for tracing.
 */
int main(void) {
    unsigned char bytes[3] = { 0, 15, 160 }; char hex[] = "0123456789ABCDEF"; char out[7]; int i = 0; for (i = 0; i < 3; ++i) { out[i * 2] = hex[bytes[i] >> 4]; out[i * 2 + 1] = hex[bytes[i] & 15]; } out[6] = 0; return out[1] == '0' && out[5] == '0' ? 0 : 1;
}

/* Discussion: inspect the loop bounds, byte classification, and final return
 * value. The bounded-C frontend currently records CIR0200 for all C source;
 * this example remains a real handbook program for the public C surface once
 * that frontend gate is restored. */
