Refactor Solver trait to streamline usage

src/solvers/cafeteria.rs

@@ -1,35 +1,19 @@
 use crate::common::interval::Interval;
 use crate::solvers::Solver;
 use std::collections::BTreeSet;
-use std::fs::File;
-use std::io;
+use std::io::BufRead;
 
-pub struct Cafeteria {
-    part1: u64,
-    part2: u64,
-}
+pub struct Cafeteria {}
 
 impl Solver for Cafeteria {
-    fn get_puzzle_index(&self) -> u8 {
-        5
-    }
-    fn get_puzzle_name(&self) -> &str {
-        "Cafeteria"
-    }
-    fn get_input_filename(&self) -> &str {
-        "cafeteria.txt"
-    }
-    fn get_part1(&self) -> u64 {
-        self.part1
-    }
-    fn get_part2(&self) -> u64 {
-        self.part2
-    }
-    fn process_data(&mut self, mut lines: io::Lines<io::BufReader<File>>) {
+    const PUZZLE_INDEX: u8 = 5;
+    const PUZZLE_NAME: &'static str = "Cafeteria";
+    const INPUT_FILENAME: &'static str = "cafeteria.txt";
+
+    fn process_data<R: BufRead>(&self, mut reader: R) -> (u64, u64) {
         // Builds intervals collection.
         let mut intervals: BTreeSet<Interval> = BTreeSet::new();
-        for line in lines
-            .by_ref()
+        for line in reader.by_ref().lines()
             .map_while(|x| x.ok().filter(|s| !s.is_empty()))
         {
             let values: Vec<u64> = line.split('-').map_while(|s| s.parse().ok()).collect();
@@ -68,19 +52,14 @@ impl Solver for Cafeteria {
             }
         }
 
+        let mut part1 = 0;
         // Tests values against intervals.
-        for value in lines.map_while(|x| x.ok()?.parse::<u64>().ok()) {
+        for value in reader.lines().map_while(|x| x.ok()?.parse::<u64>().ok()) {
             if intervals.iter().any(|interval| interval.contains(value)) {
-                self.part1 += 1;
+                part1 += 1;
             }
         }
 
-        self.part2 = intervals.iter().map(|x| x.len()).sum();
-    }
-}
-
-impl Cafeteria {
-    pub fn new() -> Cafeteria {
-        Cafeteria { part1: 0, part2: 0 }
+        (part1, intervals.iter().map(|x| x.len()).sum())
     }
 }

src/solvers/printing_department.rs

@@ -1,35 +1,21 @@
 use crate::solvers::Solver;
 use grid::*;
-use std::fs::File;
-use std::io;
+use std::io::BufRead;
 
-pub struct PrintingDepartment {
-    part1: u64,
-    part2: u64,
-}
+pub struct PrintingDepartment {}
 
 impl Solver for PrintingDepartment {
-    fn get_puzzle_index(&self) -> u8 {
-        4
-    }
-    fn get_puzzle_name(&self) -> &str {
-        "Printing Department"
-    }
-    fn get_input_filename(&self) -> &str {
-        "printing_department.txt"
-    }
-    fn get_part1(&self) -> u64 {
-        self.part1
-    }
-    fn get_part2(&self) -> u64 {
-        self.part2
-    }
-    fn process_data(&mut self, lines: io::Lines<io::BufReader<File>>) {
+    const PUZZLE_INDEX: u8 = 4;
+    const PUZZLE_NAME: &'static str = "Printing Department";
+    const INPUT_FILENAME: &'static str = "printing_department.txt";
+
+    fn process_data<R: BufRead>(&self, reader: R) -> (u64, u64) {
         let mut grid = Grid::new(0, 0);
-        for line in lines.map_while(Result::ok) {
+        for line in reader.lines().map_while(Result::ok) {
             grid.push_row(line.bytes().map(|c| c == b'@').collect());
         }
 
+        let mut part1 = 0;
         'cells: for cell in grid.indexed_iter() {
             if *cell.1 {
                 let mut count = 0;
@@ -52,14 +38,9 @@ impl Solver for PrintingDepartment {
                         }
                     }
                 }
-                self.part1 += 1;
+                part1 += 1;
             }
         }
-    }
-}
-
-impl PrintingDepartment {
-    pub fn new() -> PrintingDepartment {
-        PrintingDepartment { part1: 0, part2: 0 }
+        (part1, 0)
     }
 }

src/solvers/trash_compactor.rs

@@ -1,51 +1,32 @@
 use crate::solvers::Solver;
 use grid::*;
-use std::fs::File;
-use std::io;
+use std::io::BufRead;
 
-pub struct TrashCompactor {
-    part1: u64,
-    part2: u64,
-}
+pub struct TrashCompactor {}
 
 impl Solver for TrashCompactor {
-    fn get_puzzle_index(&self) -> u8 {
-        6
-    }
-    fn get_puzzle_name(&self) -> &str {
-        "Trash Compactor"
-    }
-    fn get_input_filename(&self) -> &str {
-        "trash_compactor.txt"
-    }
-    fn get_part1(&self) -> u64 {
-        self.part1
-    }
-    fn get_part2(&self) -> u64 {
-        self.part2
-    }
-    fn process_data(&mut self, lines: io::Lines<io::BufReader<File>>) {
+    const PUZZLE_INDEX: u8 = 6;
+    const PUZZLE_NAME: &'static str = "Trash Compactor";
+    const INPUT_FILENAME: &'static str = "trash_compactor.txt";
+
+    fn process_data<R: BufRead>(&self, reader: R) -> (u64, u64) {
+        let mut part1 = 0;
         let mut grid = Grid::new(0, 0);
-        for line in lines.map_while(Result::ok) {
+        for line in reader.lines().map_while(Result::ok) {
             let v: Vec<&str> = line.split(' ').filter(|s| !s.is_empty()).collect();
             match v[0].parse::<u32>() {
                 Ok(_) => grid.push_row(v.iter().map(|n| n.parse::<u64>().unwrap()).collect()),
                 Err(_) => {
                     for (i, sign) in v.iter().enumerate() {
                         if *sign == "+" {
-                            self.part1 += grid.iter_col(i).sum::<u64>();
+                            part1 += grid.iter_col(i).sum::<u64>();
                         } else {
-                            self.part1 += grid.iter_col(i).product::<u64>();
+                            part1 += grid.iter_col(i).product::<u64>();
                         }
                     }
                 }
             }
         }
-    }
-}
-
-impl TrashCompactor {
-    pub fn new() -> TrashCompactor {
-        TrashCompactor { part1: 0, part2: 0 }
+        (part1, 0)
     }
 }