feat: add rust solution to lcof problem: No.05 (doocs#677)

面试题 05. 替换空格

Author: YangFong

lcof/面试题05. 替换空格/README.md

@@ -151,6 +151,36 @@ function replaceSpace(s: string): string {
 }
 ```
 
+### **Rust**
+
+- 使用 `replace()`
+
+```rust
+impl Solution {
+    pub fn replace_space(s: String) -> String {
+        s.replace(' ', "%20")
+    }
+}
+```
+
+- 遍历添加
+
+```rust
+impl Solution {
+    pub fn replace_space(s: String) -> String {
+        let mut result = String::new();
+        for c in s.chars() {
+            if c == ' ' {
+                result.push_str("%20");
+            } else {
+                result.push(c);
+            }
+        }
+        result
+    }
+}
+```
+
 ### **...**
 
 ```

lcof/面试题05. 替换空格/Solution.rs

@@ -0,0 +1,5 @@
+impl Solution {
+    pub fn replace_space(s: String) -> String {
+        s.replace(' ', "%20")
+    }
+}