done

rust/clock/src/lib.rs

@@ -1,20 +1,33 @@
+use std::cmp::Ordering::{Less, Equal, Greater};
+
 #[derive(Debug)]
 pub struct Clock {
     pub hours: i32,
     pub minutes: i32,
 }
 
+/*
+    -2, -40 => 21, 20 ()
+    -47, -20 => { -20 => -48, 40  } (-47/24 => -1; -1*24 + 47  = 23; -20)
+*/
+
 impl Clock {
     pub fn new(hours: i32, minutes: i32) -> Self {
-        let hours_diff = minutes / 60;
-        let hours = hours + hours_diff;
-        let minutes = minutes - 60*hours_diff;
-        let hours_diff = hours / 24_i32;
-        let hours = hours - 24 * hours_diff;
+        let total_minutes = hours * 60 + minutes;
+        let mut total_minutes = total_minutes % 1440;
+
+        total_minutes = match total_minutes.cmp(&0) {
+            Less => total_minutes + 1440,
+            Equal | Greater => total_minutes,
+        };
+
+        let hours = total_minutes / 60;
+        let minutes = total_minutes % 60;
+
         Clock { hours, minutes }
     }
 
-    /*
+/*
     40 => 0 (0*60 + 40 - 60*0)
     60 => 1 (1*60 + 60 - 60*1)
     90 => 1 (1*60 + 90 - 60*1)
@@ -23,26 +36,19 @@ impl Clock {
     23 => 23 (23 - 24 * 0)
     26 => 2 (hours - 24 * hours_diff)
     49 => 1 (hours - 24 * hours_diff)
-    */
+*/
 
     pub fn add_minutes(&self, minutes: i32) -> Self {
-        let hours_diff: i32 = ((self.minutes + minutes) as i32) / 60_i32;
-        let hours = self.hours + hours_diff;
-        let minutes = self.minutes + minutes - 60*hours_diff;
-        let hours_diff = hours / 24_i32;
-        let hours = hours - 24 * hours_diff;
-        Clock { hours, minutes }
+        Clock::new(self.hours, self.minutes + minutes)
     }
     pub fn to_string(&self) -> String {
         let hours = match self.hours.cmp(&10) {
-            std::cmp::Ordering::Less => format!("0{}",self.hours),
-            std::cmp::Ordering::Equal => format!("{}", self.hours),
-            std::cmp::Ordering::Greater => format!("{}", self.hours),
+            Less => format!("0{}",self.hours),
+            Equal | Greater => format!("{}", self.hours),
         };
         let minutes = match self.minutes.cmp(&10) {
-            std::cmp::Ordering::Less => format!("0{}",self.minutes),
-            std::cmp::Ordering::Equal => format!("{}", self.minutes),
-            std::cmp::Ordering::Greater => format!("{}", self.minutes),
+            Less => format!("0{}",self.minutes),
+            Equal | Greater => format!("{}", self.minutes),
         };
         format!("{}:{}", hours, minutes)
     }
@@ -52,15 +58,13 @@ impl Clock {
 impl PartialEq for Clock {
     fn eq(&self, other: &Self) -> bool {
         match self.hours.cmp(&other.hours) {
-            std::cmp::Ordering::Less => false,
-            std::cmp::Ordering::Equal => {
+            Less | Greater => false,
+            Equal => {
                 match self.minutes.cmp(&other.minutes) {
-                    std::cmp::Ordering::Less => false,
-                    std::cmp::Ordering::Equal => true,
-                    std::cmp::Ordering::Greater => false,
+                    Less | Greater => false,
+                    Equal => true,
                 }
             },
-            std::cmp::Ordering::Greater => false,
         }
     }
 }