-
Notifications
You must be signed in to change notification settings - Fork 0
/
number_of_bits.cpp
62 lines (58 loc) · 1.16 KB
/
number_of_bits.cpp
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
// =====================================================================================
//
// Filename: number_of_bits.cpp
//
// Description: 191. Number of 1 Bits.
//
// Version: 1.0
// Created: 08/21/2019 08:19:00 PM
// Revision: none
// Compiler: g++
//
// Author: Zhu Xianfeng (), [email protected]
// Organization:
//
// =====================================================================================
#include <stdio.h>
#include <stdint.h>
// Iterative loop
class Solution1
{
public:
int hammingWeight(uint32_t n)
{
int m = 0;
while (n != 0)
{
if (n & 0x1)
{
m++;
}
n >>= 1;
}
return m;
}
};
// Bit manipulation trick
class Solution2
{
public:
int hammingWeight(uint32_t n)
{
int sum = 0;
while (n != 0)
{
sum++;
n &= (n - 1);
}
return sum;
}
};
using Solution = Solution2;
int main(int argc, char* argv[])
{
uint32_t n = 43261596;
int m = Solution().hammingWeight(n);
printf("%d -> %d\n", n, m);
return 0;
}