update

jhideki · jhideki · commit ad7d027cc011 · 2024-06-24T21:37:30.000-07:00
diff --git a/src/decode_ways.rs b/src/decode_ways.rs
@@ -0,0 +1,23 @@
+use std::collections::HashMap;
+pub struct Solution {}
+impl Solution {
+    pub fn num_decodings(s: String) -> i32 {
+        let s: Vec<char> = s.chars().collect();
+        let (mut d1, mut d2, mut d3) = (0, 1, 0);
+        for i in (0..s.len() as i32 - 1).rev() {
+            if s[i as usize] != '0' {
+                d1 += d2;
+            }
+            if i as usize + 1 < s.len()
+                && (s[i as usize] == '1'
+                    || s[i as usize] == '2' && s[i as usize + 1].to_digit(10).unwrap() <= 6)
+            {
+                d2 += d3;
+            }
+            d3 = d2;
+            d2 = d1;
+            d1 = 0;
+        }
+        d2
+    }
+}
diff --git a/src/main.rs b/src/main.rs
@@ -1,2 +1,2 @@
-mod palindromic_substrings;
+mod decode_ways;
 fn main() {}
