1. Set or Clear a Specific Bit in a Register

#include <stdio.h>

unsigned char modifyBit(unsigned char reg, int pos, int mode) {
    // Write your code here
    //clear that bit first
    unsigned char bitmask=1<<pos;
    reg&=(~bitmask);
    if(mode==0)return reg;
    else {
        reg|=1<<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;
}