Solve problem '191) number of 1 bits'

Author: ozantopal

problems/191-number-of-1-bits/README.md

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+Write a function that takes an unsigned integer and returns the number of '1' bits it has (also known as the [Hamming weight](https://en.wikipedia.org/wiki/Hamming_weight)).
+
+**Note:**
+
+- Note that in some languages, such as Java, there is no unsigned integer type. In this case, the input will be given as a signed integer type. It should not affect your implementation, as the integer's internal binary representation is the same, whether it is signed or unsigned.
+- In Java, the compiler represents the signed integers using [2's complement notation](https://en.wikipedia.org/wiki/Two%27s_complement). Therefore, in **Example 3**, the input represents the signed integer. `-3`.
+
+**Example 1:**
+
+```
+Input: n = 00000000000000000000000000001011
+Output: 3
+Explanation: The input binary string 00000000000000000000000000001011 has a total of three '1' bits.
+```
+
+**Example 2:**
+
+```
+Input: n = 00000000000000000000000010000000
+Output: 1
+Explanation: The input binary string 00000000000000000000000010000000 has a total of one '1' bit.
+```
+
+**Example 3:**
+
+```
+Input: n = 11111111111111111111111111111101
+Output: 31
+Explanation: The input binary string 11111111111111111111111111111101 has a total of thirty one '1' bits.
+```
+
+**Constraints:**
+
+- The input must be a **binary string** of length `32`.
+
+**Follow up:** If this function is called many times, how would you optimize it?

problems/191-number-of-1-bits/main.go

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+package main
+
+import "fmt"
+
+func main() {
+	fmt.Println(hammingWeight(11))
+	fmt.Println(hammingWeight(128))
+	fmt.Println(hammingWeight(4294967293))
+}
+
+func hammingWeight(num uint32) int {
+	count := 0
+	for num > 0 {
+		if num%2 == 1 {
+			count++
+		}
+		num /= 2
+	}
+	return count
+}