From 711badad9644d40fb258e8ac22f419d5b39537d3 Mon Sep 17 00:00:00 2001
From: David Ashby <delta.mu.alpha@gmail.com>
Date: Thu, 23 Dec 2021 18:58:54 -0700
Subject: [PATCH] 21 part 1

---
 21/main.go | 95 ++++++++++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 95 insertions(+)
 create mode 100644 21/main.go

diff --git a/21/main.go b/21/main.go
new file mode 100644
index 0000000..4a48e40
--- /dev/null
+++ b/21/main.go
@@ -0,0 +1,95 @@
+package main
+
+import (
+	"bufio"
+	"fmt"
+	"os"
+	"strconv"
+	"strings"
+	"time"
+)
+
+func mustAtoi(line string) int {
+	i, _ := strconv.Atoi(line)
+	return i
+}
+
+func main() {
+	start := time.Now()
+	partOne()
+	duration := time.Since(start)
+	partTwo()
+	duration2 := time.Since(start)
+	fmt.Printf("p1: %s, p2: %s\n", duration, duration2-duration)
+}
+
+func makeScanner(test bool) *bufio.Scanner {
+	var f *os.File
+	if test {
+		f, _ = os.Open("inputs/testinput")
+	} else {
+		f, _ = os.Open("inputs/input")
+	}
+	reader := bufio.NewReader(f)
+	return bufio.NewScanner(reader)
+}
+
+func MakeDeterministicDie(max int) func() int {
+	currentDieValue := 0
+	return func() int {
+		if currentDieValue >= max {
+			currentDieValue = 0
+		}
+		currentDieValue++
+		return currentDieValue
+	}
+}
+
+func RollThree(f func() int) int {
+	return f() + f() + f()
+}
+
+func partOne() {
+	scanner := makeScanner(false)
+
+	scanner.Scan()
+	player1 := mustAtoi(strings.Split(scanner.Text(), " ")[4])
+	scanner.Scan()
+	player2 := mustAtoi(strings.Split(scanner.Text(), " ")[4])
+
+	die := MakeDeterministicDie(100)
+	score1 := 0
+	score2 := 0
+	rolls := 0
+
+	for {
+		player1 = player1 + RollThree(die)
+		rolls += 3
+		for player1 > 10 {
+			player1 -= 10
+		}
+		score1 += player1
+		if score1 >= 1000 {
+			fmt.Println(score2 * rolls)
+			break
+		}
+		player2 = player2 + RollThree(die)
+		rolls += 3
+		for player2 > 10 {
+			player2 -= 10
+		}
+		score2 += player2
+		if score2 >= 1000 {
+			fmt.Println(score1 * rolls)
+			break
+		}
+	}
+}
+
+func partTwo() {
+	scanner := makeScanner(false)
+
+	for scanner.Scan() {
+		// line := scanner.Text()
+	}
+}