Add problem 0500: Keyboard Row

src/lib.rs

@@ -345,6 +345,7 @@ pub mod problem_0481_magical_string;
 pub mod problem_0482_license_key_formatting;
 pub mod problem_0485_max_consecutive_ones;
 pub mod problem_0498_diagonal_traverse;
+pub mod problem_0500_keyboard_row;
 pub mod problem_0503_next_greater_element_ii;
 pub mod problem_0507_perfect_number;
 pub mod problem_0513_find_bottom_left_tree_value;

src/problem_0500_keyboard_row/iterative.rs

@@ -0,0 +1,40 @@
+pub struct Solution;
+
+impl Solution {
+    pub fn find_words(words: Vec<String>) -> Vec<String> {
+        let mut chs = [0; 128];
+        let mut result = Vec::with_capacity(words.len());
+        for (idx, row) in [
+            "qwertyuiopQWERTYUIOP",
+            "asdfghjklASDFGHJKL",
+            "zxcvbnmZXCVBNM",
+        ]
+        .into_iter()
+        .enumerate()
+        {
+            row.bytes().for_each(|x| chs[x as usize] = idx);
+        }
+        for word in words {
+            let mut iter = word.bytes();
+            let row = chs[iter.next().unwrap() as usize];
+            if iter.all(|x| chs[x as usize] == row) {
+                result.push(word);
+            }
+        }
+        result
+    }
+}
+
+impl super::Solution for Solution {
+    fn find_words(words: Vec<String>) -> Vec<String> {
+        Self::find_words(words)
+    }
+}
+
+#[cfg(test)]
+mod tests {
+    #[test]
+    fn test_solution() {
+        super::super::tests::run::<super::Solution>();
+    }
+}

src/problem_0500_keyboard_row/mod.rs

@@ -0,0 +1,28 @@
+pub mod iterative;
+
+pub trait Solution {
+    fn find_words(words: Vec<String>) -> Vec<String>;
+}
+
+#[cfg(test)]
+mod tests {
+    use super::Solution;
+
+    pub fn run<S: Solution>() {
+        let test_cases = [
+            (
+                &["Hello", "Alaska", "Dad", "Peace"] as &[_],
+                &["Alaska", "Dad"] as &[_],
+            ),
+            (&["omk"], &[]),
+            (&["adsdf", "sfd"], &["adsdf", "sfd"]),
+        ];
+
+        for (words, expected) in test_cases {
+            assert_eq!(
+                S::find_words(words.iter().copied().map(str::to_string).collect()),
+                expected
+            );
+        }
+    }
+}