diff --git a/src/day02/src/part02b.rs b/src/day02/src/part02b.rs
index 15aa998..ca83120 100644
--- a/src/day02/src/part02b.rs
+++ b/src/day02/src/part02b.rs
@@ -11,7 +11,7 @@ pub fn day02b() -> u64 {
     let mut nr_or_correct_reports: u64 = 0;
     // iterate over all reports
     file_content.split("\n").for_each(|report| {
-        let mut levels: Vec<i32> = report.split(" ").map(|level| level.parse::<i32>().unwrap()).collect();
+        let levels: Vec<i32> = report.split(" ").map(|level| level.parse::<i32>().unwrap()).collect();
         let mut trend: i32 = 0;
         let mut safe: i32 = 2;
         // iterate over all levels and ty to find a trend
diff --git a/src/main.rs b/src/main.rs
index d8da1b7..d650b24 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -1,11 +1,24 @@
+use std::iter::zip;
+use std::time::Instant;
 use day01::part01a::day01a;
 use day01::part01b::day01b;
 use day02::part02a::day02a;
 use day02::part02b::day02b;
 
 fn main() {
-    println!("day01:A =>  {}", day01a());
-    println!("day01:B =>  {}", day01b());
-    println!("day02:A =>  {}", day02a());
-    println!("day02:B =>  {}", day02b());
+    let exercises: Vec<(&str, fn () -> u64)> = vec![
+        ("day01:A", day01a),
+        ("day01:B", day01b),
+        ("day02:A", day02a),
+        ("day02:B", day02b),
+    ];
+
+    let start: Instant = Instant::now();
+    exercises.iter().for_each(|(day, func)| {
+        let day_start: Instant = Instant::now();
+        println!("{:7} => {:10}  ({:6}us)", day, func(), day_start.elapsed().as_micros());
+    });
+
+    println!("                       ----------");
+    println!("                       {:7}us", start.elapsed().as_micros());
 }