binary-search

binary-search/sol.rs

@@ -0,0 +1,24 @@
+use std::cmp::Ordering;
+
+impl Solution {
+    pub fn search(mut nums: Vec<i32>, target: i32) -> i32 {
+        // nums.len() > 0 so this is safe to do
+        if *nums.first().unwrap_or(&-target) == target {
+            return 0;
+        }
+        let mut current = nums.as_slice();
+        let mut idx = 0;
+        while current.len() > 1 {
+            let m = current.len() / 2;
+            match target.cmp(&current[m]) {
+                Ordering::Equal => return (idx + m) as i32,
+                Ordering::Greater => {
+                    current = current.split_at(m).1;
+                    idx += m;
+                },
+                Ordering::Less => current = current.split_at(m).0
+            }
+        }
+        -1
+    }
+}