3228. 将 1 移动到末尾的最大操作次数

src/main.rs

@@ -1,38 +1,26 @@
-use std::collections::HashSet;
-
 struct Solution;
 impl Solution {
-    pub fn count_palindromic_subsequence(s: String) -> i32 {
+    pub fn max_operations(s: String) -> i32 {
+        let s = s.as_bytes();
         let mut ans = 0;
-        let s = s.bytes().collect::<Vec<u8>>();
-        let mut set : HashSet<u8> = HashSet::new();
-        for c in b'a'..=b'z' {
-            set.clear();
-            let (mut start,mut end) = (-1,0);
-            for i in 0..s.len() {
-                if s[i] == c {
-                    start = i as i32;
-                    break;
+        let mut ones  = 0;
+        let mut first_zero = false;
+        for i in 0..s.len() {
+            if s[i] ==b'1' {
+                ones += 1;
+                first_zero = true;
+            }
+            else {
+                if first_zero {
+                    ans += ones;
+                    first_zero = false;
                 }
             }
-            if start == -1 {
-                continue;
-            }
-            for i in (0..s.len()).rev() {
-                if s[i] == c {
-                    end = i;
-                    break;
-                }
-            }
-            for i in (start+1)as usize..end {
-                set.insert(s[i]);
-            }
-            ans += set.len() as i32;
         }
         ans
     }
 }
 fn main() {
-    let result = Solution::count_palindromic_subsequence(String::from("bbcbaba"));
+    let result = Solution::max_operations(String::from("1001101"));
     println!("{:?}", result);
 }