1. Set or Clear a Specific Bit in a Register

#include <stdio.h>

unsigned char modifyBit(unsigned char reg, int pos, int mode) {
    if(mode){
        reg &= 0b11111111;
    }
    else if(mode == 0){
        reg &=~(1 << pos); // 0b00001010 & 0b1111 0111 = 0b0000 0010 
    }
    return reg; 
}

int main() {
    unsigned char reg = 10;
    int pos = 3 ; 
    int mode = 0; 
    reg = modifyBit(reg,pos,mode);
    scanf("%d %d %d", &reg, &pos, &mode);
    printf("%d", modifyBit(reg, pos, mode));
    return 0;

}