Day 3 Swift

Swift/2020-code-advent.playground/Contents.swift

@@ -1,7 +1,11 @@
-print(advent01.day_01_01())
+//print(advent01.day_01_01())
+//
+//print(advent01.day_01_02())
+//
+//print(advent02.day_02_01())
+//
+//print(advent02.day_02_02())
 
-print(advent01.day_01_02())
+print(advent03.day_03_01())
 
-print(advent02.day_02_01())
-
-print(advent02.day_02_02())
+print(advent03.day_03_02())

Swift/2020-code-advent.playground/Sources/03-01.swift

@@ -0,0 +1,65 @@
+import Foundation
+
+public class advent03 {
+  
+  static func count_trees(orig_map: [String], slope_x: Int, slope_y : Int) -> Int {
+    
+    let m_cols = orig_map[0].count
+    let m_rows = orig_map.count
+    let n_tiles = ((slope_x + 1) * m_rows) / (m_cols)
+    
+    let actual_map = orig_map.map { String(repeating: $0, count: n_tiles) }
+
+//    actual_map.forEach{ debugPrint($0) }
+//    debugPrint(actual_map[0].count)
+
+    var xpos = 0
+    var ypos = 0
+    var n_trees = 0
+
+    while(true) {
+
+      xpos += slope_x
+      ypos += slope_y
+
+      if (ypos >= m_rows) { break }
+      
+      let rowidx = actual_map[ypos].index(actual_map[ypos].startIndex, offsetBy: xpos)
+//      debugPrint("rowidx: \(rowidx.encodedOffset); y: \(ypos); m_rows: \(m_rows); [\(actual_map[ypos][rowidx])]")
+
+      if (actual_map[ypos][rowidx] == "#") { n_trees += 1 }
+
+    }
+    
+    return(n_trees)
+    
+  }
+  
+  public static func day_03_01() -> Int {
+    guard let orig_map = try? String(contentsOfFile: "/Users/hrbrmstr/Development/2020-code-advent/input/03-01.txt", encoding: .utf8)
+            .components(separatedBy: "\n")  else {
+      return(-1)
+    }
+    
+    return(count_trees(orig_map: orig_map.filter { line in line != "" }, slope_x: 3, slope_y: 1))
+    
+  }
+  
+  public static func day_03_02() -> Int {
+    guard let orig_map = try? String(contentsOfFile: "/Users/hrbrmstr/Development/2020-code-advent/input/03-01.txt", encoding: .utf8)
+            .components(separatedBy: "\n")  else {
+      return(-1)
+    }
+    
+    let x = [ 1, 3, 5, 7, 1 ]
+    let y = [ 1, 1, 1, 1, 2 ]
+
+    let res = stride(from: 0, to: x.count, by: 1).map { row in
+      count_trees(orig_map: orig_map.filter { line in line != "" }, slope_x: x[row], slope_y: y[row])
+    }.reduce(1, { a, b in a * b })
+    
+    return(res)
+    
+  }
+  
+}

scala/03/.metals/metals.lock.db

@@ -1,6 +0,0 @@
-#FileLock
-#Sat Dec 05 05:30:36 EST 2020
-server=localhost\:52514
-hostName=localhost
-method=file
-id=176327412afbfda2d2c304a27da7b2246bc93fbaf1f