Solve valid-anagram.

source/lib.rs

@@ -7,4 +7,5 @@ pub mod plus_one;
 pub mod reverse_integer;
 pub mod roman_to_integer;
 pub mod two_sum;
+pub mod valid_anagram;
 pub mod valid_parenthesis;

source/valid_anagram/mod.rs

@@ -0,0 +1,31 @@
+pub fn is_anagram(a: String, b: String) -> bool {
+  // Both strings must have the same length otherwise they can't be anagrams.
+  if a.len() != b.len() {
+    return false;
+  }
+
+  // Sort both strings' characters so they're in alphabetical order.
+  let mut a = a.chars().collect::<Vec<_>>();
+  a.sort();
+
+  let mut b = b.chars().collect::<Vec<_>>();
+  b.sort();
+
+  // And if they are equal, then they're anagrams.
+  a == b
+}
+
+#[test]
+fn test_valid_anagram() {
+  let samples = [
+    (("💖🌠banana", "an💖anab🌠"), true),
+    (("anagram", "nagaram"), true),
+    (("bats", "tabs"), true),
+    (("rat", "cat"), false),
+    (("bats", "bat"), false),
+  ];
+
+  for ((a, b), expected) in samples {
+    assert_eq!(is_anagram(a.to_string(), b.to_string()), expected);
+  }
+}