a solution to pwc 096.2 in rust

1 files changed, 35 insertions, 0 deletions

diff --git a/challenge-096/gugod/rust/ch-2.rs b/challenge-096/gugod/rust/ch-2.rs
new file mode 100644
index 0000000000..7a6761191a
--- /dev/null
+++ b/challenge-096/gugod/rust/ch-2.rs
@@ -0,0 +1,35 @@
+
+fn main() {
+    let examples: [[&str; 2]; 2] = [
+        ["kitten", "sitting"],
+        ["sunday", "monday"],
+    ];
+    for x in examples.iter() {
+        println!("Input: S1={}, S2={}", x[0], x[1]);
+        println!("Output: {}", edit_distance(x[0], x[1]));
+    }
+}
+
+fn edit_distance(a: &str, b: &str) -> u32 {
+    let chars_a = a.chars().collect();
+    let chars_b = b.chars().collect();
+    return lev( &chars_a, 0, &chars_b, 0);
+}
+
+fn lev (a: &Vec<char>, offset_a: usize, b: &Vec<char>, offset_b: usize) -> u32 {
+    if offset_a == a.len() {
+        return (b.len() - offset_b) as u32;
+    }
+    if offset_b == b.len() {
+        return (a.len() - offset_a) as u32;
+    }
+
+    let n3 = lev( a, offset_a+1, b, offset_b+1 );
+    if a[offset_a] == b[offset_b] {
+        return n3;
+    } else {
+        let n1 = lev( a, offset_a+1, b, offset_b );
+        let n2 = lev( a, offset_a,   b, offset_b+1 );
+        return [n1, n2, n3].iter().min().unwrap() + 1_u32;
+    }
+}