1. Set or Clear a Specific Bit in a Register

#include <stdio.h> 

#define BIT_SET(reg,pos)   ((reg) |= (1 << (pos))) 
#define BIT_CLEAR(reg,pos) ((reg) &= ~ (1 << (pos))) 

unsigned char modifyBit(unsigned char reg, int pos, int mode) {
    // Write your code here  
    if (mode == 1) 
      BIT_SET(reg,pos);
     else 
       BIT_CLEAR(reg,pos);
       return reg; 
   
}

int main() {
    unsigned char reg;
    int pos, mode;
    scanf("%hhu %d %d", &reg, &pos, &mode);
    printf("%d", modifyBit(reg, pos, mode));
    return 0;
}