From 5ce9bc821b38ad1f4677ad178b5cad7d1208aef6 Mon Sep 17 00:00:00 2001
From: iByteABit256 <paulsmith4561@gmail.com>
Date: Tue, 14 Feb 2023 00:12:21 -0800
Subject: [PATCH] Performance improvement

---
 Cargo.lock  | 2 +-
 Cargo.toml  | 3 ++-
 src/main.rs | 6 ++----
 3 files changed, 5 insertions(+), 6 deletions(-)

diff --git a/Cargo.lock b/Cargo.lock
index 9b53d4d..9d2511a 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -284,7 +284,7 @@ dependencies = [
 
 [[package]]
 name = "mrn-generator"
-version = "0.1.0"
+version = "0.2.0"
 dependencies = [
  "chrono",
  "clap",
diff --git a/Cargo.toml b/Cargo.toml
index 3e1ee32..7a8a864 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -1,7 +1,8 @@
 [package]
 name = "mrn-generator"
-version = "0.1.0"
+version = "0.2.0"
 edition = "2021"
+authors = ["Pavlos Smith <paulsmith4561+at+gmail.com>"]
 
 # See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
 
diff --git a/src/main.rs b/src/main.rs
index ee0c176..6133d28 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -28,10 +28,8 @@ fn is_mrn_valid(mrn: &str) -> Option<char> {
 
     let mrn_temp: String = mrn_iter.collect();
 
-    // Powers of 2
-    let multipliers: Vec<u32> = (0..mrn_temp.len()).map(|n| 1 << n).collect();
-
-    let multiplied_sum: u32 = mrn_temp.chars().zip(multipliers).map(|(c,m)| check_character_value(c) as u32 * m).sum();
+    // Multiply each char value with it's power of 2 and sum them
+    let multiplied_sum: u32 = mrn_temp.chars().zip(0..mrn_temp.len()).map(|(c,m)| (check_character_value(c) as u32) << m).sum();
 
     let check_digit: u8 = (multiplied_sum % 11).try_into().unwrap();
     check_remainder_value(check_digit, last_digit)