"C" Enter an integer that outputs the number of 1 in the binary representation (three methods)

Enter an integer that outputs the number of 1 in the binary representation. such as input 32, output 1.

Code implementation:

Method 1: and operation

#define _crt_secure_no_warnings 1#include<iostream>using namespace Std;int findonenumber (unsigned int num) {int n    Umberofone = 0;        while (num) {num = num & (num-1);    numberofone++; } return numberofone;}    void Test () {int num = 32; Cout<<findonenumber (num) <<endl;}    int main () {Test ();    System ("pause"); return 0;}

Method 2: modulo Division

#define _crt_secure_no_warnings 1#include<iostream>using namespace Std;int findonenumber (unsigned int num) {int n    Umberofone = 0;        while (num) {if (num% 2 = = 1) numberofone++;    Num/= 2; } return numberofone;}    void Test () {int num = 32; cout << findonenumber (num) << Endl;}    int main () {Test ();    System ("pause"); return 0;}

Method 3: shift

#define _crt_secure_no_warnings 1#include<iostream>using namespace Std;int findonenumber (unsigned int num) {int n    Umberofone = 0;        while (num) {if (num & 1) numberofone++;    num = num >> 1; } return numberofone;}    void Test () {int num = 32; cout << findonenumber (num) << Endl;}    int main () {Test ();    System ("pause"); return 0;}

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"C" Enter an integer that outputs the number of 1 in the binary representation (three methods)