C language practice small code---Six

1. Write a function to return the number of 1's in the parameter binary,
such as: 15 0000 1111 4 1
program prototype:
int count_one_bits(unsigned int value)
{
// return the number of 1 bits
}

#define _CRT_SECURE_NO_WARNINGS ch
#include<stdio.h>
#include<Windows.h>
#include<math.h>
#include<time.h>
//Write a function to return the number of 1's in the parameter binary
//For example: 15 0000 1111 4 1s
//Program prototype:
int count_one_bits(unsigned int value)
{
	int i = 0;
	int count = 0;
	for (i = 0; i < 32; i++){
		if (1 == ((value >> i) & 1)){
			count++;
		}
	}
	return count;
}
int main(){
	int value = 15;
	int ret = count_one_bits(value);
	printf("%d\n", ret);
	system("pause");
	return 0;
}

Running result: (Test case: if input 15, it should output 4)

2. Get all the even and odd bits in a binary sequence of numbers, and output the binary sequence respectively.

#define _CRT_SECURE_NO_WARNINGS ch
#include<stdio.h>
#include<Windows.h>
#include<math.h>
#include<time.h>
//Get all the even and odd bits in a binary sequence of numbers, and output the binary sequence respectively.
int main(){
	int i = 0;
	int value = 15;
	for (i = 0; i < 32; i+=2){
		printf("%d ", (value >> i) & 1);
	}
	printf("\n");
	for (i = 1; i < 32; i += 2){
		printf("%d ", (value >> i) & 1);
	}
	system("pause");
	return 0;
}

3. Print each bit of an integer. (recursive implementation)

#define _CRT_SECURE_NO_WARNINGS ch
#include<stdio.h>
#include<Windows.h>
#include<math.h>
#include<time.h>
// Output each bit of an integer. (recursive)
void print(int num){
	if (num >9){
		print(num/10);
	}
	printf("%d", num % 10);
}
int main(){
	int num = 1234;
	print(num);
	system("pause");
	return 0;
}

4. Programming implementation:
How many bits are different in the binary representation of two int (32-bit) integers m and n?
Input example:
1999 2299
Output example: 7

#define _CRT_SECURE_NO_WARNINGS ch
#include<stdio.h>
#include<Windows.h>
#include<math.h>
#include<time.h>
//Programming implementation:
//How many bits are different in the binary representation of two int (32-bit) integers m and n?
//input example:
//1999 2299
//Example of output: 7
int main(){
	int a = 1999;
	int b = 2299;
	int i = 0;
	int count = 0;
	for (i = 0; i < 32; i++){
		if (1 == ((a >> i) & 1) ^ ((b >> i) & 1)){
			count++;
		}
	}
	printf("%d", count);
	system("pause");
	return 0;
}

Experimental results: