Stop combining if finished, update layouts between x and y

src/combine-layouts.rs

@@ -7,6 +7,11 @@ mod city;
 mod db;
 mod combine;
 
+#[derive(Eq, PartialEq)]
+enum LastStep {
+    None, Vertical, Horizontal
+}
+
 fn main() {
     let mut db = LayoutDB::from_file("layouts.sqlite").expect("Failed to load the DB");
     eprintln!("Loaded the DB, {} stored layouts", db.layouts().len());
@@ -18,22 +23,36 @@ fn main() {
     let transposed_city = transpose_city(&city);
     eprintln!("Finished building a transposed city");
 
+    const TOP_LAYOUT_COUNT: usize = 100;
+
+    let mut last_improve_step = LastStep::None;
     loop {
+        if last_improve_step == LastStep::Vertical { break; }
+        eprintln!("Starting to combine {} top houses DB; vertical cuts", TOP_LAYOUT_COUNT);
         let sorted: Vec<_> = db.layouts().iter()
             .sorted_by(|x, y| city::get_price(&city, x.houses()).cmp(&city::get_price(&city, y.houses())))
             .map(|layout| layout.clone())
             .collect();
-
-        const TOP_LAYOUT_COUNT: usize = 1000;
-
         let chosen_layouts: Vec<_> = sorted.iter().take(TOP_LAYOUT_COUNT).map(|l| l.houses().clone()).collect();
+        if combine::try_combine(&city, &chosen_layouts, &chosen_layouts, &mut db, false) {
+            last_improve_step = LastStep::Vertical;
+        }
+        eprintln!("Finished vertical cuts, improvement: {}", last_improve_step == LastStep::Vertical);
 
-        eprintln!("Starting to combine {} top houses DB; vertical cuts", TOP_LAYOUT_COUNT);
-        combine::try_combine(&city, &chosen_layouts, &chosen_layouts, &mut db, false);
+        if last_improve_step == LastStep::Horizontal { break; }
 
+        let sorted: Vec<_> = db.layouts().iter()
+            .sorted_by(|x, y| city::get_price(&city, x.houses()).cmp(&city::get_price(&city, y.houses())))
+            .map(|layout| layout.clone())
+            .collect();
+        let chosen_layouts: Vec<_> = sorted.iter().take(TOP_LAYOUT_COUNT).map(|l| l.houses().clone()).collect();
         let transposed_chosen_layouts: Vec<_> = chosen_layouts.iter().map(|x| transpose_layout(x)).collect();
+
         eprintln!("Starting to combine {} top houses DB; horizontal cuts", TOP_LAYOUT_COUNT);
-        combine::try_combine(&transposed_city, &transposed_chosen_layouts, &transposed_chosen_layouts, &mut db, true);
+        if combine::try_combine(&transposed_city, &transposed_chosen_layouts, &transposed_chosen_layouts, &mut db, true) {
+            last_improve_step = LastStep::Horizontal;
+        }
+        eprintln!("Finished horizontal cuts, improvement: {}", last_improve_step == LastStep::Horizontal);
     }
 }
 

src/combine.rs

@@ -6,7 +6,9 @@ use itertools::iproduct;
 use std::collections::VecDeque;
 use std::collections::vec_deque::Iter;
 
-pub fn try_combine(city: &City, left_layouts: &Vec<Vec<House>>, right_layouts: &Vec<Vec<House>>, db: &mut LayoutDB, transposed: bool) {
+pub fn try_combine(city: &City, left_layouts: &Vec<Vec<House>>, right_layouts: &Vec<Vec<House>>, db: &mut LayoutDB, transposed: bool) -> bool {
+    let mut improved = false;
+
     // Sorted in reverse so we can remove from the end
     let mut left_houses_sorted: Vec<Vec<House>> = left_layouts.iter()
         .map(|l| l.iter().sorted_by(|h1, h2| h2.x.cmp(&h1.x)).map(|x| *x).collect())
@@ -35,13 +37,11 @@ pub fn try_combine(city: &City, left_layouts: &Vec<Vec<House>>, right_layouts: &
         .map(|layout| city::get_price(&city, layout))
         .min();
 
+    let axis = if transposed { "y" } else { "x" };
+
     // x is the last left coordinate, x+1 is right
     for x in 0..SIZE {
-        if transposed {
-            eprintln!("Starting y {}", x);
-        } else {
-            eprintln!("Starting x {}", x);
-        }
+        eprintln!("Starting {} {}", axis, x);
 
         // Update the lines
         for (left_line, left_houses) in lefts.iter_mut().zip(left_houses_sorted.iter_mut()) {
@@ -78,9 +78,8 @@ pub fn try_combine(city: &City, left_layouts: &Vec<Vec<House>>, right_layouts: &
             if is_compatible(city, &left, &right) {
                 if best_price.is_none() || price < best_price.unwrap() {
                     best_price = Some(price);
-                    let axis = if transposed { "y" } else { "x" };
-                    eprintln!("{} - new best score, cut on {} {}, left {} - right {}, printing", axis, price, x, left_i, right_i);
-                    println!("{} - new best score, cut on {} {}, left {} - right {}", axis, price, x, left_i, right_i);
+                    eprintln!("{} - new best score, cut on {} {}, left {} - right {}, printing", price, axis, x, left_i, right_i);
+                    println!("{} - new best score, cut on {} {}, left {} - right {}", price, axis, x, left_i, right_i);
                     let mut new_houses: Vec<_> = left.houses().copied().chain(right.houses().copied()).collect();
                     if transposed {
                         new_houses = transpose_layout(&new_houses);
@@ -92,6 +91,7 @@ pub fn try_combine(city: &City, left_layouts: &Vec<Vec<House>>, right_layouts: &
 
                     // We only add best results to avoid overfilling the database with similar layouts
                     db.add_layout(&new_houses, true);
+                    improved = true;
                 }
                 compatibles += 1;
 
@@ -104,6 +104,8 @@ pub fn try_combine(city: &City, left_layouts: &Vec<Vec<House>>, right_layouts: &
 
         eprintln!("{} incompatibles checked before {} compatible", incompatibles, compatibles);
     }
+
+    improved
 }
 
 fn is_compatible(city: &City, left: &LeftLine, right: &RightLine) -> bool {