From 579535c553176e475ec31b1d060e73c98edb584c Mon Sep 17 00:00:00 2001
From: martabal <74269598+martabal@users.noreply.github.com>
Date: Mon, 2 Dec 2024 11:26:44 +0100
Subject: [PATCH] fix: optimize day01

---
 Cargo.lock               |  2 +-
 c/day01.c                | 10 ++--------
 cpp/day01.cc             | 12 +++++-------
 crates/day01/Cargo.toml  |  2 +-
 crates/day01/src/main.rs | 10 ++++------
 5 files changed, 13 insertions(+), 23 deletions(-)

diff --git a/Cargo.lock b/Cargo.lock
index f0f5232..0d10fd5 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -4,7 +4,7 @@ version = 4
 
 [[package]]
 name = "day01"
-version = "0.1.0"
+version = "0.1.1"
 
 [[package]]
 name = "day02"
diff --git a/c/day01.c b/c/day01.c
index dbfe14b..79192bb 100644
--- a/c/day01.c
+++ b/c/day01.c
@@ -56,18 +56,14 @@ int main() {
   qsort(left_column, len, sizeof(int), compare_ints);
   qsort(right_column, len, sizeof(int), compare_ints);
 
-  unsigned int *distances = malloc(len * sizeof(unsigned int));
   unsigned int sum = 0;
 
   for (size_t i = 0; i < len; i++) {
-    distances[i] = abs(left_column[i] - right_column[i]);
-    sum += distances[i];
+    sum += abs(left_column[i] - right_column[i]);
   }
   printf("Part One solution: sum is %u\n", sum);
-  free(distances);
 
   // --- Part Two ---
-  unsigned int *appear = malloc(len * sizeof(unsigned int));
   sum = 0;
 
   for (size_t i = 0; i < len; i++) {
@@ -77,12 +73,10 @@ int main() {
         count++;
       }
     }
-    appear[i] = left_column[i] * count;
-    sum += appear[i];
+    sum += left_column[i] * count;
   }
 
   printf("Part Two solution: sum is %u\n", sum);
-  free(appear);
   free(left_column);
   free(right_column);
 
diff --git a/cpp/day01.cc b/cpp/day01.cc
index 3b67595..9aa3af8 100644
--- a/cpp/day01.cc
+++ b/cpp/day01.cc
@@ -33,7 +33,7 @@ read_file(const std::string &input) {
 int main() {
   // --- Part One ---
   auto [left_column, right_column] = read_file("crates/day01/input.txt");
-  std::vector<unsigned int> distances;
+  unsigned int sum = 0;
 
   if (left_column.size() != right_column.size()) {
     throw std::runtime_error("Column sizes do not match");
@@ -43,22 +43,20 @@ int main() {
   std::sort(right_column.begin(), right_column.end());
 
   for (size_t i = 0; i < left_column.size(); ++i) {
-    distances.push_back(
-        static_cast<unsigned int>(std::abs(left_column[i] - right_column[i])));
+    sum +=
+        (static_cast<unsigned int>(std::abs(left_column[i] - right_column[i])));
   }
 
-  unsigned int sum = std::accumulate(distances.begin(), distances.end(), 0u);
   std::cout << "Part One solution: sum is " << sum << std::endl;
 
   // --- Part Two ---
+  sum = 0;
   std::vector<unsigned int> appear;
   for (const auto &e : left_column) {
     unsigned int count =
         std::count(right_column.begin(), right_column.end(), e);
-    appear.push_back(static_cast<unsigned int>(e) * count);
+    sum += static_cast<unsigned int>(e) * count;
   }
-
-  sum = std::accumulate(appear.begin(), appear.end(), 0);
   std::cout << "Part Two solution: sum is " << sum << std::endl;
 
   return 0;
diff --git a/crates/day01/Cargo.toml b/crates/day01/Cargo.toml
index f02b6c7..3888ec6 100644
--- a/crates/day01/Cargo.toml
+++ b/crates/day01/Cargo.toml
@@ -1,6 +1,6 @@
 [package]
 name = "day01"
-version = "0.1.0"
+version = "0.1.1"
 edition = "2021"
 
 [lints]
diff --git a/crates/day01/src/main.rs b/crates/day01/src/main.rs
index 99c5c76..408d362 100644
--- a/crates/day01/src/main.rs
+++ b/crates/day01/src/main.rs
@@ -4,7 +4,6 @@ use std::io::{self, BufRead};
 fn main() {
     // --- Part One ---
     let (mut left_column, mut right_column) = read_file("crates/day01/input.txt").unwrap();
-    let mut distances: Vec<u32> = Vec::new();
 
     assert!(left_column.len() == right_column.len());
     #[cfg(feature = "unstable")]
@@ -20,14 +19,14 @@ fn main() {
         right_column.sort();
     }
 
+    let mut sum: i32 = 0;
     for (i, _) in left_column.iter().enumerate() {
-        distances.push((left_column[i] - right_column[i]).unsigned_abs());
+        sum += (left_column[i] - right_column[i]).abs();
     }
-    let mut sum: u32 = distances.iter().copied().sum();
     println!("Part One solution: sum is {sum}");
 
     // --- Part Two ---
-    let mut appear: Vec<u32> = Vec::new();
+    sum = 0;
     for e in &left_column {
         let count: i32 = right_column
             .iter()
@@ -35,9 +34,8 @@ fn main() {
             .count()
             .try_into()
             .unwrap();
-        appear.push((*e * count).try_into().unwrap());
+        sum += *e * count;
     }
-    sum = appear.iter().copied().sum();
     println!("Part Two solution: sum is {sum}");
 }