refmt

Author: 0xmountaintop

kamyu104/src/bitwise_and_of_numbers_range.rs

@@ -2,8 +2,6 @@
 // Space: O(1)
 
 pub struct Solution1 {}
-pub struct Solution2 {}
-
 impl Solution1 {
     pub fn range_bitwise_and(m: u32, mut n: u32) -> u32 {
         while m < n {
@@ -14,6 +12,7 @@ impl Solution1 {
     }
 }
 
+pub struct Solution2 {}
 impl Solution2 {
     pub fn range_bitwise_and(m: u32, n: u32) -> u32 {
         let (mut i, mut diff): (u32, u32) = (0, n - m);

kamyu104/src/number_of_1_bits.rs

@@ -2,7 +2,6 @@
 // Space: O(1)
 
 pub struct Solution {}
-
 impl Solution {
     pub fn hamming_weight(mut n: u32) -> u8 {
         let mut cnt: u8 = 0;

kamyu104/src/power_of_two.rs

@@ -1 +1,35 @@
+// Time:  O(1)
+// Space: O(1)
+
+pub struct Solution1 {}
+impl Solution1 {
+    pub fn is_power_of_two(n: i32) -> bool {
+        n > 0 && (n & (n - 1)) == 0
+    }
+}
+
+pub struct Solution2 {}
+impl Solution2 {
+    pub fn is_power_of_two(n: i32) -> bool {
+        n > 0 && (n & !-n) == 0
+    }
+}
+
+
+#[cfg(test)]
+mod tests {
+    // Note this useful idiom: importing names from outer (for mod tests) scope.
+    use super::*;
+
+    #[test]
+    fn test_is_power_of_two() {
+        assert_eq!(Solution1::is_power_of_two(1), true);
+        assert_eq!(Solution1::is_power_of_two(16), true);
+        assert_eq!(Solution1::is_power_of_two(218), false);
+
+        assert_eq!(Solution2::is_power_of_two(1), true);
+        assert_eq!(Solution2::is_power_of_two(16), true);
+        assert_eq!(Solution2::is_power_of_two(218), false);
+    }
+}
 

kamyu104/src/reverse_bits.rs

@@ -2,7 +2,6 @@
 // Space: O(1)
 
 pub struct Solution {}
-
 impl Solution {
     pub fn reverse_bits(mut n: u32) -> u32 {
         let mut result: u32 = 0;

kamyu104/src/single_number.rs

@@ -2,7 +2,6 @@
 // Space: O(1)
 
 pub struct Solution {}
-
 impl Solution {
     pub fn single_number(nums: Vec<i32>) -> i32 {
         nums.iter().fold(0, |acc, &num| acc ^ num)

kamyu104/src/single_number_ii.rs

@@ -4,10 +4,6 @@
 use std::collections::HashSet;
 
 pub struct Solution1 {}
-pub struct Solution2 {}
-pub struct Solution3 {}
-pub struct Solution4 {}
-
 impl Solution1 {
     pub fn single_number(nums: Vec<i32>) -> i32 {
         let (mut one, mut two): (i32, i32) = (0, 0);
@@ -21,6 +17,7 @@ impl Solution1 {
     }
 }
 
+pub struct Solution2 {}
 impl Solution2 {
     pub fn single_number(nums: Vec<i32>) -> i32 {
         let (mut one, mut two, mut carry): (i32, i32, i32) = (0, 0, 0);
@@ -36,11 +33,13 @@ impl Solution2 {
 }
 
 // https://github.com/kamyu104/LeetCode-Solutions/blob/master/Python/single-number-ii.py#L31
+// pub struct Solution3 {}
 // impl Solution3 {
 //     pub fn single_number(nums: Vec<i32>) -> i32 {
 //     }
 // }
 
+pub struct Solution4 {}
 impl Solution4 {
     pub fn single_number(nums: Vec<i32>) -> i32 {
         let sum: i32 = nums.iter().sum();

kamyu104/src/template.rs

@@ -1,5 +1,4 @@
 pub struct Solution {}
-
 impl Solution {
     pub fn add(a: i32, b: i32) -> i32 {
         // only print when a test fails