20240508 Finished

src/problem/mod.rs

@@ -124,4 +124,5 @@ mod p73_set_matrix_zeroes;
 mod p289_game_of_life;
 mod p383_ransom_note;
 mod p290_word_pattern;
-mod p205_isomorphic_strings;
+mod p205_isomorphic_strings;
+mod p242_valid_anagram;

src/problem/p242_valid_anagram.rs

@@ -0,0 +1,49 @@
+/**
+ * [242] Valid Anagram
+ */
+pub struct Solution {}
+
+
+// submission codes start here
+use std::collections::HashMap;
+
+impl Solution {
+    pub fn is_anagram(s: String, t: String) -> bool {
+        let mut map = HashMap::new();
+
+        for c in s.chars() {
+            let entry = map.entry(c).or_insert(0);
+
+            *entry += 1;
+        }
+
+        for c in t.chars() {
+            match map.get_mut(&c) {
+                Some(value) => {
+                    *value -= 1;
+
+                    if *value == 0 {
+                        map.remove(&c);
+                    }
+                },
+                None => {
+                    return false;
+                }
+            }
+        }
+
+        map.len() == 0
+    }
+}
+
+// submission codes end
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn test_242() {
+        assert!(Solution::is_anagram("anagram".to_owned(), "nagaram".to_owned()));
+    }
+}