Initial commit (day 01)

Signed-off-by: Christopher Arndt <chris@chrisarndt.de>

day_01/solution_01.nim

@@ -0,0 +1,12 @@
+import std/[re, strutils]
+
+var res = 0
+
+for line in readFile("input_01.txt").splitLines:
+    if line.strip.len > 0:
+        var digits = findAll(line, re"\d")
+        var number = parseInt(digits[0] & digits[^1])
+        res += number
+        #echo $digits, $number
+
+echo "Result: ", $res

day_01/solution_01b.nim

@@ -0,0 +1,20 @@
+import std/[re, strutils]
+
+var res = 0
+var valid_digits = "one,two,three,four,five,six,seven,eight,nine".split(",")
+var digits_rx = re("\\d|" & valid_digits.join("|"))
+
+proc parseDigit(s: string): int =
+    try:
+        result = parseInt(s)
+    except ValueError:
+        result = valid_digits.find(s) + 1
+
+for line in readFile("input_01.txt").splitLines:
+    if line.strip.len > 0:
+        var digits = findAll(line, digits_rx)
+        var number = parseDigit(digits[0]) * 10 + parseDigit(digits[^1])
+        res += number
+        #echo $digits, $number
+
+echo "Result: ", $res