Solve isomorphic-strings.

source/isomorphic_strings/mod.rs

@@ -0,0 +1,15 @@
+pub fn is_isomorphic(a: String, b: String) -> bool {
+  let mut map_a = std::collections::HashMap::new();
+  let mut map_b = std::collections::HashMap::new();
+
+  for (a, b) in a.chars().zip(b.chars()) {
+    let from_map_a = *map_a.entry(a).or_insert(b);
+    let from_map_b = *map_b.entry(b).or_insert(a);
+
+    if from_map_b != a || from_map_a != b {
+      return false;
+    }
+  }
+
+  true
+}

source/lib.rs

@@ -2,6 +2,7 @@ pub mod add_binary;
 pub mod excel_sheet_column_number;
 pub mod excel_sheet_column_title;
 pub mod implement_strstr;
+pub mod isomorphic_strings;
 pub mod length_of_last_word;
 pub mod longest_common_prefix;
 pub mod missing_number;

tests/isomorphic_strings.rs

@@ -0,0 +1,11 @@
+use leetcode::isomorphic_strings::is_isomorphic;
+
+use test_case::test_case;
+
+#[test_case("egg", "add", true; "valid")]
+#[test_case("foo", "bar", false; "invalid")]
+#[test_case("badc", "baba", false; "map both ways")]
+#[test_case("paper", "title", true; "different maps")]
+fn test_isomorphic_strings(a: &str, b: &str, expected: bool) {
+  assert_eq!(is_isomorphic(a.to_string(), b.to_string()), expected);
+}