2018 Day 01 Complete (go)

2018/day01/day01.go

@@ -0,0 +1,60 @@
+package main
+
+import (
+	"bufio"
+	"fmt"
+	"log"
+	"os"
+	"strconv"
+)
+
+func main() {
+	inp := StdinToStringSlice()
+	part1(inp)
+	part2(inp)
+}
+
+func part1(inp []string) {
+	freq := 0
+	for _, v := range inp {
+		freq += Atoi(v)
+	}
+	fmt.Println("Part 1:", freq)
+}
+
+func part2(inp []string) {
+	fmt.Println("Part 2:", findRepeat(inp))
+}
+
+func findRepeat(inp []string) int {
+	vals := make(map[int]bool)
+	freq := 0
+	for true {
+		for _, v := range inp {
+			freq += Atoi(v)
+			if vals[freq] {
+				return freq
+			}
+			vals[freq] = true
+		}
+	}
+	return 0
+}
+
+func StdinToStringSlice() []string {
+	var input []string
+	scanner := bufio.NewScanner(os.Stdin)
+	for scanner.Scan() {
+		input = append(input, scanner.Text())
+	}
+	return input
+}
+
+func Atoi(i string) int {
+	var ret int
+	var err error
+	if ret, err = strconv.Atoi(i); err != nil {
+		log.Fatal("Invalid Atoi")
+	}
+	return ret
+}