advent-of-code

commit 96935fb8eb497d4d111e645ffc57b8e0792fea56
parent 54fe807e4d4c175d1c433b3a7cc7c5ee0a4805a6
Author: finwo <finwo@pm.me>
Date:   Thu, 15 Dec 2022 14:06:26 +0100

Optimized step 1 of 2022/15

Diffstat:
M
2022/day-15/index.js
 | 
65
++++++++++++++++++++++-------------------------------------------

1 file changed, 22 insertions(+), 43 deletions(-)
diff --git a/2022/day-15/index.js b/2022/day-15/index.js
@@ -40,12 +40,6 @@ fs.createReadStream('input')
       parseInt(beaconTokens[6].replace(/[^\d\-]/g, '')),
     ];
 
-    // // Track in visual representation
-    // rows[sensorPosition[1]] = rows[sensorPosition[1]] || [];
-    // rows[sensorPosition[1]][sensorPosition[0]] = 'S';
-    // rows[beaconPosition[1]] = rows[beaconPosition[1]] || [];
-    // rows[beaconPosition[1]][beaconPosition[0]] = 'B';
-
     // Calculate distance between beacon and sensor
     const d = Math.abs(sensorPosition[0] - beaconPosition[0]) + Math.abs(sensorPosition[1] - beaconPosition[1]);
 
@@ -55,22 +49,10 @@ fs.createReadStream('input')
       d,
     });
 
-    // // Mark locations that can NOT have a beacon (step 1)
-    // for(let y=sensorPosition[1]-d; y<=sensorPosition[1]+d; y++) {
-    //   if (!small && y !== scanline) continue;
-    //   const X = d - Math.abs(sensorPosition[1] - y);
-    //   for(let x=sensorPosition[0]-X; x<=sensorPosition[0]+X; x++) {
-    //     const D = Math.abs(sensorPosition[0] - x) + Math.abs(sensorPosition[1] - y);
-    //     if (D > d) continue;
-    //     rows[y] = rows[y] || [];
-    //     rows[y][x] = rows[y][x] || '#';
-    //   }
-    // }
-
-    // xmin = Math.min(xmin, sensorPosition[0]-d, beaconPosition[0]-d);
-    // ymin = Math.min(ymin, sensorPosition[1]-d, beaconPosition[1]-d);
-    // xmax = Math.max(xmax, sensorPosition[0]+d, beaconPosition[0]+d);
-    // ymax = Math.max(ymax, sensorPosition[1]+d, beaconPosition[1]+d);
+    xmin = Math.min(xmin, sensorPosition[0]-d, beaconPosition[0]-d);
+    ymin = Math.min(ymin, sensorPosition[1]-d, beaconPosition[1]-d);
+    xmax = Math.max(xmax, sensorPosition[0]+d, beaconPosition[0]+d);
+    ymax = Math.max(ymax, sensorPosition[1]+d, beaconPosition[1]+d);
 
     // console.log({ sensorTokens, sensorPosition, beaconTokens, beaconPosition, d });
     cb();
@@ -79,29 +61,26 @@ fs.createReadStream('input')
   .on('finish', () => {
     console.log('loaded');
 
-    xmin -= 2;
-    ymin -= 2;
-    xmax += 2;
-    ymax += 2;
-
-    // Debug display for small
-    if (small) {
-      for(let y=ymin; y<=ymax; y++) {
-        if (!rows[y]) {
-          process.stdout.write('.'.repeat(xmax-xmin+1) + '\n');
-          continue;
-        }
-        for(let x=xmin; x<=xmax; x++) {
-          if (rows[y][x]) {
-            process.stdout.write(rows[y][x]);
-          } else {
-            process.stdout.write('.');
-          }
-        }
-        process.stdout.write(`  ${y}\n`);
-      }
+    // Step 1
+    let covered = -1;
+    for(let x=xmin; x<=xmax; x++) {
+
+      const found = sensors.find(sensor => {
+        const d = Math.abs(sensor.pos[0] - x) + Math.abs(sensor.pos[1] - scanline);
+        return d <= sensor.d;
+      });
+
+      if (!found) continue;
+
+      // Add width at current Y and skip steps
+      const X = found.d - Math.abs(found.pos[1] - scanline);
+      covered += (found.pos[0] - x) + 1 + X;
+      x = found.pos[0] + X;
     }
 
+    console.log({ covered });
+
+
     // Step 2
     for(let y=0; y<=interestingArea; y++) {
       // console.log(y);