Merge pull request #19 from jtr109/reverse-words-in-a-string-iii

Reverse words in a string iii

Author: jtr109

Cargo.lock

@@ -10,4 +10,5 @@ members = [
     "merge_sorted_array",
     "intersection_of_two_arrays",
     "longest_palindromic_substring",
+    "reverse_words_in_a_string_iii",
 ]

Cargo.toml

@@ -16,6 +16,7 @@ Resolving problems of LeetCode in RustLang.
 * [215. Kth Largest Element in an Array](./kth_largest/src/lib.rs)
 * [232. Implement Queue using Stacks](./implement_queue_using_stacks/src/lib.rs)
 * [349. Intersection of Two Arrays](./intersection_of_two_arrays/src/lib.rs)
+* [557. Reverse Words in a String III](./reverse_words_in_a_string_iii/src/lib.rs)
 
 ## Document
 

README.md

@@ -0,0 +1,9 @@
+[package]
+name = "reverse_words_in_a_string_iii"
+version = "0.1.0"
+authors = ["Ryan Li <conbas2019@gmail.com>"]
+edition = "2018"
+
+# See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
+
+[dependencies]

reverse_words_in_a_string_iii/Cargo.toml

@@ -0,0 +1,53 @@
+/*!
+ * # 557. Reverse Words in a String III
+ *
+ * [Problem link](https://leetcode.com/problems/reverse-words-in-a-string-iii/)
+ */
+
+#![allow(dead_code)]
+
+struct Solution {}
+
+// ----------------------------------------------------------------------------
+
+impl Solution {
+    pub fn reverse_words(s: String) -> String {
+        let mut i = 0;
+        let chars = s.chars().collect::<Vec<char>>();
+        let mut reversed = vec![];
+        while i < s.len() {
+            if chars[i] == ' ' {
+                reversed.push(chars[i]);
+                i += 1;
+                continue;
+            }
+            let mut j = i;
+            while j < s.len() && chars[j] != ' ' {
+                j += 1;
+            }
+            let mut k = j - 1;
+            loop {
+                // push the char into the reversed vector until reach the index `i`
+                reversed.push(chars[k]);
+                if k == i {
+                    break;
+                }
+                k -= 1;
+            }
+            i = j;
+        }
+        reversed.iter().collect()
+    }
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn test_example_1() {
+        let input = "Let's take LeetCode contest".to_string();
+        let output = "s'teL ekat edoCteeL tsetnoc".to_string();
+        assert_eq!(Solution::reverse_words(input), output);
+    }
+}