LC 1957. Delete Characters to Make Fancy String (Rust)

Author: raul-sauco

README.md

@@ -640,6 +640,7 @@ to the solution in this repository.
 | [1937. Maximum Number of Points with Cost][lc1937]                                            | 🟠 Medium  | [![rust](res/rs.png)][lc1937rs]                                                                       |
 | [1942. The Number of the Smallest Unoccupied Chair][lc1942]                                   | 🟠 Medium  | [![rust](res/rs.png)][lc1942rs]                                                                       |
 | [1945. Sum of Digits of String After Convert][lc1945]                                         | 🟢 Easy    | [![rust](res/rs.png)][lc1945rs]                                                                       |
+| [1957. Delete Characters to Make Fancy String][lc1957]                                        | 🟢 Easy    | [![rust](res/rs.png)][lc1957rs]                                                                       |
 | [1962. Remove Stones to Minimize the Total][lc1962]                                           | 🟠 Medium  | [![python](res/py.png)][lc1962py]                                                                     |
 | [1963. Minimum Number of Swaps to Make the String Balanced][lc1963]                           | 🟠 Medium  | [![rust](res/rs.png)][lc1963rs]                                                                       |
 | [1964. Find the Longest Valid Obstacle Course at Each Position][lc1964]                       | 🔴 Hard    | [![python](res/py.png)][lc1964py] [![rust](res/rs.png)][lc1964rs]                                     |
@@ -2190,6 +2191,8 @@ to the solution in this repository.
 [lc1942rs]: leetcode/the-number-of-the-smallest-unoccupied-chair.rs
 [lc1945]: https://leetcode.com/problems/sum-of-digits-of-string-after-convert/
 [lc1945rs]: leetcode/sum-of-digits-of-string-after-convert.rs
+[lc1957]: https://leetcode.com/problems/delete-characters-to-make-fancy-string/
+[lc1957rs]: leetcode/delete-characters-to-make-fancy-string.rs
 [lc1962]: https://leetcode.com/problems/remove-stones-to-minimize-the-total/
 [lc1962py]: leetcode/remove-stones-to-minimize-the-total.py
 [lc1963]: https://leetcode.com/problems/minimum-number-of-swaps-to-make-the-string-balanced/

leetcode/delete-characters-to-make-fancy-string.rs

@@ -0,0 +1,66 @@
+// 1957. Delete Characters to Make Fancy String
+// 🟢 Easy
+//
+// https://leetcode.com/problems/delete-characters-to-make-fancy-string/
+//
+// Tags: String
+
+struct Solution;
+impl Solution {
+    /// Iterate over the input counting the frequency of characters, append to the result string
+    /// while the current character is repeated a maximum of 2 times.
+    ///
+    /// Time complexity: O(n)
+    /// Space complexity: O(n)
+    ///
+    /// Runtime 2 ms Beats 100%
+    /// Memory 2.51 MB Beats 28.57%
+    pub fn make_fancy_string(s: String) -> String {
+        let mut res = String::with_capacity(s.len());
+        let mut last = '?';
+        let mut repeated = false;
+        for c in s.chars() {
+            if c == last {
+                if repeated {
+                    continue;
+                }
+                repeated = true;
+            } else {
+                last = c;
+                repeated = false;
+            }
+            res.push(c);
+        }
+        res
+    }
+}
+
+// Tests.
+fn main() {
+    let tests = [("leeetcode", "leetcode"), ("aaabaaaa", "aabaa")];
+    println!("\n\x1b[92m» Running {} tests...\x1b[0m", tests.len());
+    let mut success = 0;
+    for (i, t) in tests.iter().enumerate() {
+        let res = Solution::make_fancy_string(t.0.to_string());
+        if res == t.1 {
+            success += 1;
+            println!("\x1b[92m✔\x1b[95m Test {} passed!\x1b[0m", i);
+        } else {
+            println!(
+                "\x1b[31mx\x1b[95m Test {} failed expected: {:?} but got {}!!\x1b[0m",
+                i, t.1, res
+            );
+        }
+    }
+    println!();
+    if success == tests.len() {
+        println!("\x1b[30;42m✔ All tests passed!\x1b[0m")
+    } else if success == 0 {
+        println!("\x1b[31mx \x1b[41;37mAll tests failed!\x1b[0m")
+    } else {
+        println!(
+            "\x1b[31mx\x1b[95m {} tests failed!\x1b[0m",
+            tests.len() - success
+        )
+    }
+}