Write a javascript function that takes an integer as input, and returns the number of bits that are equal to one in the binary representation of that number. You can guarantee that input is non-negative. Example: The binary representation of 1234 is 10011010010, so the function should return 5 in this case
时间: 2024-04-02 20:36:44 浏览: 56
Sure, here's a JavaScript function that takes an integer as input and returns the number of bits that are equal to one in its binary representation:
```javascript
function countBits(num) {
// Convert the number to binary string
let binary = num.toString(2);
// Count the number of ones in the binary string
let count = 0;
for (let i = 0; i < binary.length; i++) {
if (binary[i] === '1') {
count++;
}
}
return count;
}
```
You can call this function with an integer as input, like this:
```javascript
console.log(countBits(1234)); // Output: 5
```
This will output `5`, which is the number of bits that are equal to one in the binary representation of `1234`.
相关问题
Write a function, is_prime, that takes a single integer argument and returns True when the argument is a prime number and False otherwise.
Sure! Here's the Python code for the is_prime function:
```
def is_prime(n):
if n <= 1:
return False
for i in range(2, int(n**0.5) + 1):
if n % i == 0:
return False
return True
```
This function takes a single integer argument `n` and returns `True` when `n` is a prime number and `False` otherwise. The function first checks if `n` is less than or equal to 1, as 1 is not a prime number. Then it loops through all the integers from 2 to the square root of `n`, checking if any of them divide `n` without a remainder. If any such integer is found, `n` is not a prime number and the function returns `False`. Otherwise, `n` is a prime number and the function returns `True`.
Write a python function proddigits() that inputs a positive integer number and returns the product of digits of that number. For example, if the input is 422, the function should return 16 (which is equal to 4×2×2 ).
Here's one way to write the `proddigits()` function in Python:
```python
def proddigits(num):
"""Returns the product of the digits in a positive integer number."""
product = 1 # start with a product of 1
while num > 0:
digit = num % 10 # extract the rightmost digit
product *= digit # multiply the product by the digit
num //= 10 # remove the rightmost digit from the number
return product
```
You can call this function with a positive integer argument to get the product of its digits:
```python
print(proddigits(422)) # Output: 16
print(proddigits(12345)) # Output: 120
print(proddigits(987654321)) # Output: 362880
```
The function works by iterating over the digits of the input number using a while loop. In each iteration, it extracts the rightmost digit using the modulo operator (`%`) and multiplies the product by that digit. Then it removes the rightmost digit from the number using integer division (`//`). The loop continues until there are no more digits left in the number. Finally, the function returns the product of all the digits.