boilerplate: add timing

boilerplate/src/main.rs

@@ -1,5 +1,6 @@
 use std::fs::File;
 use std::io::{BufRead, BufReader, Lines};
+use std::time::{Duration, Instant};
 
 // BOILERPLATE
 type InputIter = Lines<BufReader<File>>;
@@ -11,8 +12,15 @@ fn get_input() -> InputIter {
 }
 
 fn main() {
-    println!("Problem 1 solution: {}", problem1(get_input()));
-    println!("Problem 2 solution: {}", problem2(get_input()));
+    let start = Instant::now();
+    let ans1 = problem1(get_input());
+    let duration = start.elapsed();
+    println!("Problem 1 solution: {} [{}s]", ans1, duration.as_secs_f64());
+
+    let start = Instant::now();
+    let ans2 = problem2(get_input());
+    let duration = start.elapsed();
+    println!("Problem 2 solution: {} [{}s]", ans2, duration.as_secs_f64());
 }
 
 // PROBLEM 1 solution