20240812 Finished

src/problem/mod.rs

@@ -202,3 +202,4 @@ mod p120_triangle;
 mod p64_minimum_path_sum;
 mod p63_unique_paths_ii;
 mod p97_interleaving_string;
+mod p72_edit_distance;

src/problem/p72_edit_distance.rs

@@ -0,0 +1,57 @@
+/**
+ * [72] Edit Distance
+ */
+pub struct Solution {}
+
+
+// submission codes start here
+
+impl Solution {
+    pub fn min_distance(word1: String, word2: String) -> i32 {
+        let (word1, word2): (Vec<char>, Vec<char>) = (word1.chars().collect(), word2.chars().collect());
+        let (n, m) = (word1.len(), word2.len());
+        
+        // 存在一个字符串有空串
+        if m * n == 0 {
+            return (m + n) as i32;
+        }
+        
+        let mut dp = vec![vec![0;m + 1]; n + 1];
+        
+        // 初始化dp数组
+        for i in 0..=n {
+            dp[i][0] = i;
+        }
+        
+        for i in 0..=m {
+            dp[0][i] = i;
+        }
+        
+        for i in 1..=n {
+            for j in 1..=m {
+                let left = dp[i - 1][j] + 1;
+                let down = dp[i][j - 1] + 1;
+                let mut left_down = dp[i - 1][ j -1];
+                if word1[i - 1] != word2[j - 1] {
+                    left_down += 1;
+                }
+                
+                dp[i][j] = left.min(down).min(left_down);
+            }
+        }
+        
+        dp[n][m] as i32
+    }
+}
+
+// submission codes end
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn test_72() {
+        assert_eq!(3, Solution::min_distance("horse".to_owned(), "ros".to_owned()));
+    }
+}