docs: clarify timings

Author: fspoettel

README.md

@@ -9,11 +9,11 @@
 
 ---
 
-Generated with the [advent-of-code-rust](https://github.com/fspoettel/advent-of-code-rust) template.
+Generated from [fspoettel/advent-of-code-rust](https://github.com/fspoettel/advent-of-code-rust).
 
 ## Create your own
 
- 1. Open the [advent-of-code-rust](https://github.com/fspoettel/advent-of-code-rust) template on Github.
+ 1. Open ☝️ template on Github.
  2. Click `Use this template` and create your repository.
  3. Clone the repository to your machine.
 
@@ -41,6 +41,8 @@ Generated with the [advent-of-code-rust](https://github.com/fspoettel/advent-of-
 # 🎄 Type `cargo run --bin 01` to run your solution.
 ```
 
+Individual solutions live in the `./src/bin` directory as separate binaries.
+
 Every [solution](https://git.io/JyXa8) has _unit tests_ referencing the _example_ file. Use these tests to develop and debug your solution. When editing a solution, `rust-analyzer` will display buttons for these actions above the unit tests.
 
 ### Download inputs for a day
@@ -81,6 +83,8 @@ cargo run --bin <day>
 
 To run an optimized version for benchmarking, use the `--release` flag or the alias `cargo rr --bin <day>`.
 
+Displayed _timings_ show the raw execution time of your solution w/o overhead (e.g. file reads).
+
 ### Run solutions for all days
 
 ```sh
@@ -104,6 +108,8 @@ cargo run
 
 To run an optimized version for benchmarking, use the `--release` flag or the alias `cargo rr`.
 
+_Total timing_ is computed from individual solution _timings_ and excludes overhead.
+
 ### Run all solutions against example input
 
 ```sh

src/lib.rs

@@ -15,10 +15,10 @@ macro_rules! solve {
         fn print_result<T: Display>(func: impl FnOnce(&str) -> T, input: &str) {
             let timer = Instant::now();
             let result = func(input);
-            let time = timer.elapsed();
+            let elapsed = timer.elapsed();
             println!(
                 "{} {}(elapsed: {:.2?}){}",
-                result, ANSI_ITALIC, time, ANSI_RESET
+                result, ANSI_ITALIC, elapsed, ANSI_RESET
             );
         }