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 == 0)
    {
        // Clear the bit
        // printf("Before: %d\n", reg);
        reg &= ~(1 << pos);
        // printf("After: %d\n", reg);
    } else if(mode == 1)
    {
        // Set the bit
        // printf("Before: %d\n", reg);
        reg |= (1 << pos);
        // printf("After: %d\n", reg);
    }else
    {
        printf("Wrong mode given");
        return -1;
    }
    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;
}