Merge pull request #956 from bus710/week08

[bus710] Week 08

Author: bus710

number-of-1-bits/bus710.rs

@@ -0,0 +1,34 @@
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn it_works() {
+        let result = Solution::hamming_weight(11);
+        assert_eq!(result, 3);
+        let result = Solution::hamming_weight(128);
+        assert_eq!(result, 1);
+        let result = Solution::hamming_weight(2147483645);
+        assert_eq!(result, 30);
+    }
+}
+
+#[derive(Debug)]
+struct Solution;
+
+#[allow(dead_code)]
+impl Solution {
+    pub fn hamming_weight(n: i32) -> i32 {
+        let mut cnt: i32 = 0;
+        let mut target_bit_holder: i32;
+
+        for i in 0..32 {
+            target_bit_holder = n & (0x1 << i);
+            if target_bit_holder != 0 {
+                cnt += 1;
+            }
+        }
+
+        cnt
+    }
+}