Validate Configuration Register Layout

Code

#include <stdio.h>

typedef struct {
    unsigned short reg;
} ConfigRegister;

int validate_config(ConfigRegister *cfg) {
    // Bit 0 must be 1
    if ((cfg->reg & 0x01) != 1)
        return 0;

    // Bits 2-3 must not be 11
    if ((cfg->reg & 0x0C) == 0x0C)
        return 0;

    // Bits 4-15 must be 0
    if ((cfg->reg & 0xFFF0) != 0)
        return 0;

    return 1;  // All conditions satisfied
}


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

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

    return 0;
}

Solving Approach