Validate Configuration Register Layout

Code

#include <stdio.h>
#include <stdint.h>
typedef struct {
    unsigned short reg;
} ConfigRegister;

typedef union {
    uint16_t reg;
    struct{
    uint8_t enable :1;
    uint8_t mode :1;
    uint8_t priority :2;
    uint16_t reserved :12;
    };
} useful;
int validate_config(ConfigRegister *cfg) {
    // Write logic using pointer access
    useful a;
    a.reg = cfg->reg;
    if(a.enable == 1 && a.priority <3 && a.reserved == 0)
        return 1;
    return 0;
}

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

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

    return 0;
}

Solving Approach