77. Validate Configuration Register Layout

#include <stdio.h>

typedef struct {
    unsigned short reg;

} ConfigRegister;

int validate_config(ConfigRegister *cfg) {
    // Write logic using pointer access
    unsigned short value;

    value = cfg->reg;   //(*cfg).reg;
    /*       
    if((value & 1)||((value&0x000c)!= 0xc)||((value>>3)==0))
        return 1;
    else
        return 0;
    */
    
    // Check if Enable bit is set (bit 0)
    if ((value & 0x0001) == 0)
        return 0;

    // Extract priority (bits 2–3)
    unsigned short priority = (value >> 2) & 0x03;
    if (priority == 0x03)  // Invalid priority
        return 0;

    // Check reserved bits (bits 4–15) are all 0
    if ((value & 0xFFF0) != 0)
        return 0;

    return 1;

}

int main() {
    ConfigRegister cfg;
    scanf("%hx", &cfg.reg);

    int result = validate_config(&cfg);
    printf("%d", result);

    return 0;
}