feat: word_ladder

src/solutions/bfs/mod.rs

@@ -0,0 +1 @@
+mod word_ladder;

src/solutions/bfs/word_ladder.rs

@@ -0,0 +1,65 @@
+struct Solution;
+
+impl Solution {
+    pub fn ladder_length(begin_word: String, end_word: String, word_list: Vec<String>) -> i32 {
+
+        let mut queue = std::collections::VecDeque::new();
+        let mut visited = std::collections::HashSet::new();
+        queue.push_back((&begin_word, 1));
+
+        while let Some((src, idx)) = queue.pop_front() {
+            if end_word.eq(src) {
+                return idx;
+            }
+
+            if !visited.insert(src) {
+                continue;
+            }
+
+            for word in &word_list {
+                if Solution::is_ladder_str(src.as_bytes(), word.as_bytes()) {
+                    queue.push_back((word, idx + 1));
+                }
+
+
+            }
+        }
+        0
+
+    }
+
+    fn is_ladder_str(src: &[u8], dst: &[u8]) -> bool {
+        if src.len() != dst.len() {
+            return false;
+        }
+
+        let mut idx = 0;
+
+        for i in 0..src.len() {
+            if idx > 1 {
+                return false;
+            }
+
+            if src[i] != dst[i] {
+                idx += 1;
+            }
+        }
+
+
+        idx == 1
+    }
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn test_ladder_length() {
+        let begin_word = String::from("hit");
+        let end_word = String::from("cog");
+        let word_list = vec![String::from("hot"),String::from("dot"),String::from("dog"),String::from("lot"),String::from("log"),String::from("cog")];
+        let res = Solution::ladder_length(begin_word, end_word, word_list);
+        assert_eq!(res, 5);
+    }
+}

src/solutions/mod.rs

@@ -32,6 +32,7 @@ mod three_sum_closest;
 mod two_sum;
 mod valid_parenthese;
 mod zigzag_conversion;
+mod bfs;
 
 // Definition for singly-linked list.
 #[derive(PartialEq, Eq, Clone, Debug)]