C programming example implementing a function to set a specified bit in an int (from ECE 2534), C (gcc)

C programming example implementing a function to set a specified bit in an int (from ECE 2534)

// Example program that implements the function setBit(x, i) 
// that returns the value of x with the bit at index i set to a 1, 
// where 0 <= i <= 31. All other bits in x should be left unchanged.
// -----------------------------------------------------------------
// To run the program in rextester, you will need to enter the
// bit number and the integer value to test as a hex number in the input window
// That is, type something into the "Show input" window, e.g., "6 0xFFFF0000"

#include  <stdio.h>

// horrible recursive helper function to print int as binary
void printBinary(unsigned int number)
{
    if (number) {
        printBinary(number >> 1);
        putc((number & 1) ? '1' : '0', stdout);
    }
}

// my setBit function
int setBit(int x, int i)
{
    int returnValue;
    int bitMask;
    // set bit mask
    bitMask = (1 << i);
    // set the bit from the bit mask using a bitwise OR
    returnValue = x | bitMask;
    return(returnValue);
}

int main(void)
{
    unsigned int initialValue, returnedValue;
    int n;
    printf("Remember to input the bit number to set and the hex number in the input window!\n\n");
    // read in the value as a hex number
    scanf("%d %x\n", &n, &initialValue);
    // print out bit that will be cleared
    printf("Bit to be set is %d\n",n);
    // print out the value read in as a binary number
    printf("Input:  ");
    printBinary(initialValue);
    // set bit n
    returnedValue = setBit(initialValue, n);
    // print out the returned value as a binary number
    printf("\nOutput: ");
    printBinary(returnedValue);
    return 0;
}


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