括号匹配精简实现代码

rust/src/implements/q0020.rs

@@ -36,47 +36,12 @@ impl Solution {
     /// * 👍 2979
     /// * 👎 0
     pub fn is_valid(s: String) -> bool {
+        if s.len() & 1 == 1 { return false; }
         let mut v = vec![];
-        for c in s.chars() {
-            match c as char {
-                '(' | '[' | '{' => v.push(c),
-                ')' => {
-                    match v.last() {
-                        None => return false,
-                        Some(s) => {
-                            if *s == '(' {
-                                v.pop();
-                            } else {
-                                return false;
-                            }
-                        }
-                    }
-                }
-                ']' => {
-                    match v.last() {
-                        None => return false,
-                        Some(s) => {
-                            if *s == '[' {
-                                v.pop();
-                            } else {
-                                return false;
-                            }
-                        }
-                    }
-                }
-                '}' => {
-                    match v.last() {
-                        None => return false,
-                        Some(s) => {
-                            if *s == '{' {
-                                v.pop();
-                            } else {
-                                return false;
-                            }
-                        }
-                    }
-                }
-                _ => (),
+        for c in s.into_bytes() {
+            match c {
+                b'(' | b'[' | b'{' => v.push(c + (1 << (c & 1))),
+                _ => if Some(c) != v.pop() { return false }
             }
         }
         v.is_empty()