77. Validate Configuration Register Layout

#include <stdio.h>

#define data (cfg -> reg)

typedef struct {
    unsigned short reg;
} ConfigRegister;

int validate_config(ConfigRegister *cfg) {
    if((data & 1) == 0) return 0;
    if((data & 12) == 12) return 0;
    if((data >> 4) != 0) return 0;
    return 1;
}

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

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

    return 0;
}