Bit Operations using Macros

Code

#include <stdio.h>
#include <stdint.h>

// Define bitwise macros here
#define SET_BIT(reg, pos)     ((reg) |  (1 << (pos)))
#define CLEAR_BIT(reg, pos)   ((reg) & ~(1 << (pos)))
#define TOGGLE_BIT(reg, pos)  ((reg) ^  (1 << (pos)))

uint8_t modify_register(uint8_t reg) {
    reg = SET_BIT(reg, 2);
    reg = SET_BIT(reg, 7);
    reg = CLEAR_BIT(reg, 3);
    reg = TOGGLE_BIT(reg, 5);
    return reg;
}

int main() {
    uint8_t reg;
    scanf("%hhu", &reg);
    printf("%u", modify_register(reg));
    return 0;
}

Solving Approach

• Use bitwise macros:
  • SET_BIT(reg, bit) → (reg | (1 << bit))
  • CLEAR_BIT(reg, bit) → (reg & ~(1 << bit))
  • TOGGLE_BIT(reg, bit) → (reg ^ (1 << bit))
• Apply operations in order:
  • Set bits 2 and 7
  • Clear bit 3
  • Toggle bit 5
• Return final register value.