Merge pull request #200 from 0xff-dev/master

Add solution and test-cases for problem 205

Author: Cori1109

leetcode/201-300/0205.Isomorphic-Strings/README.md

@@ -1,26 +1,32 @@
 # [205.Isomorphic Strings][title]
 
-> [!WARNING|style:flat]
-> This question is temporarily unanswered if you have good ideas. Welcome to [Create Pull Request PR](https://github.com/kylesliu/awesome-golang-algorithm)
 
 ## Description
+Given two strings `s` and `t`, determine if they are isomorphic.
+
+Two strings `s` and `t` are isomorphic if the characters in `s` can be replaced to get `t`.
+
+All occurrences of a character must be replaced with another character while preserving the order of characters. No two characters may map to the same character, but a character may map to itself.
 
 **Example 1:**
 
 ```
-Input: a = "11", b = "1"
-Output: "100"
+Input: s = "egg", t = "add"
+Output: true
 ```
 
-## 题意
-> ...
+**Example 2:**
+
+```
+Input: s = "foo", t = "bar"
+Output: false
+```
 
-## 题解
+**Example 3:**
 
-### 思路1
-> ...
-Isomorphic Strings
-```go
+```
+Input: s = "paper", t = "title"
+Output: true
 ```
 
 

leetcode/201-300/0205.Isomorphic-Strings/Solution.go

@@ -1,5 +1,27 @@
 package Solution
 
-func Solution(x bool) bool {
-	return x
+func Solution(s string, t string) bool {
+	ls, lt := len(s), len(t)
+	if ls != lt {
+		return false
+	}
+
+	mapping := make(map[byte]byte)
+	reverseMapping := make(map[byte]struct{})
+	for idx := 0; idx < ls; idx++ {
+		if v, ok := mapping[s[idx]]; ok {
+			if v != t[idx] {
+				return false
+			}
+			continue
+		}
+		if _, ok := reverseMapping[t[idx]]; ok {
+			return false
+		}
+
+		mapping[s[idx]] = t[idx]
+		reverseMapping[t[idx]] = struct{}{}
+	}
+
+	return true
 }

leetcode/201-300/0205.Isomorphic-Strings/Solution_test.go

@@ -10,21 +10,24 @@ func TestSolution(t *testing.T) {
 	//	测试用例
 	cases := []struct {
 		name   string
-		inputs bool
+		s, t   string
 		expect bool
 	}{
-		{"TestCase", true, true},
-		{"TestCase", true, true},
-		{"TestCase", false, false},
+		{"TestCase1", "egg", "add", true},
+		{"TestCase2", "foo", "bar", false},
+		{"TestCase3", "bar", "foo", false},
+		{"TestCase4", "paper", "title", true},
+		{"TestCase5", "title", "paper", true},
+		{"TestCase6", "abcd", "efgh", true},
 	}
 
 	//	开始测试
 	for i, c := range cases {
 		t.Run(c.name+" "+strconv.Itoa(i), func(t *testing.T) {
-			got := Solution(c.inputs)
+			got := Solution(c.s, c.t)
 			if !reflect.DeepEqual(got, c.expect) {
-				t.Fatalf("expected: %v, but got: %v, with inputs: %v",
-					c.expect, got, c.inputs)
+				t.Fatalf("expected: %v, but got: %v, with inputs: %v %v",
+					c.expect, got, c.s, c.t)
 			}
 		})
 	}