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
    switch(mode)
    {
        // clear bit
        case(0):
        {
            return reg & ~(1U << pos);
            break;
        }

        // set bit
        default:
        {
            return reg | (1U << pos);
            break;
        }
    }
}

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