C++

1class Solution {
2public:
3    int numberOfSteps (int num) {
4        int cnt = 0;
5        while (num > 0) {
6            if (num&1 == 1) --num;
7            else num >>= 1;
8            
9            ++cnt;
10        }
11        return cnt;
12    }
13};

JavaScript

1var numberOfSteps  = function(num) {
2    let cnt = 0;
3    
4    while (num > 0) {
5        if ((num & 1) == 0) num = num / 2;
6        else num -= 1;
7        ++cnt;
8    }
9    
10    return cnt;
11};

Ruby

1# Runtime: 48 ms, faster than 84.85%
2# Memory Usage: 209.6 MB, less than 70.71%
3def number_of_steps (num)
4    cnt = 0
5    while (num > 0) do 
6        if num%2 == 0
7            num = num / 2
8        else 
9            num -= 1
10        end
11        
12        cnt += 1
13    end
14    cnt
15end
16
17# usnig BITWISE OPERATOR
18# Runtime: 40 ms, faster than 95.96%
19# Memory Usage: 209.6 MB, less than 70.71%
20def number_of_steps (num)
21    cnt = 0
22    while (num > 0) do 
23        if num&1 == 0
24            num = num >> 1 
25        else 
26            num -= 1
27        end
28        
29        cnt += 1
30    end
31    cnt
32end