77. Validate Configuration Register Layout

#include <stdio.h>

typedef struct {
    unsigned short reg;
} ConfigRegister;

union {
    struct {
    unsigned short en : 1;
    unsigned short mode : 1;
    unsigned short priority : 2;
    unsigned short reserved : 12;
    }bits;
    unsigned short val;
}temp;
int validate_config(ConfigRegister *cfg) {
    // Write logic using pointer access
    temp.val =  cfg->reg;
    if(temp.bits.en == 1 && temp.bits.priority != 0x3 && temp.bits.reserved == 0) return 1;
    return 0;
}

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

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

    return 0;
}