Added recursion solution

tim-harding · Sep 6, 2023 · 4ac3d79 · 4ac3d79
1 parent 1494166
commit 4ac3d79
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Showing 2 changed files with 19 additions and 2 deletions.
diff --git a/src/problems/_08_recursion_and_dynamic_programming/_01_triple_step.rs b/src/problems/_08_recursion_and_dynamic_programming/_01_triple_step.rs
@@ -11,7 +11,7 @@ impl TripleStep for Solution {
     fn triple_step(steps: usize) -> usize {
         // Your solution here
         use crate::solutions::_08_recursion_and_dynamic_programming::_01_triple_step as solutions;
-        solutions::Solution::triple_step(steps)
+        solutions::RecursionSolution::triple_step(steps)
     }
 }
 

diff --git a/src/solutions/_08_recursion_and_dynamic_programming/_01_triple_step.rs b/src/solutions/_08_recursion_and_dynamic_programming/_01_triple_step.rs
@@ -5,7 +5,7 @@ pub struct Solution;
 impl TripleStep for Solution {
     fn triple_step(steps: usize) -> usize {
         match steps {
-            0 => 0,
+            0 => 1,
             1 => 1,
             2 => 2,
             3 => 4,
@@ -27,3 +27,20 @@ impl TripleStep for Solution {
         }
     }
 }
+
+pub struct RecursionSolution;
+
+impl TripleStep for RecursionSolution {
+    fn triple_step(steps: usize) -> usize {
+        match steps {
+            0 => 1,
+            1 => 1,
+            2 => 2,
+            _ => {
+                Self::triple_step(steps - 1)
+                    + Self::triple_step(steps - 2)
+                    + Self::triple_step(steps - 3)
+            }
+        }
+    }
+}