2017 Day 02 Completed in Go

2017/day02/day02.go

@@ -0,0 +1,95 @@
+package main
+
+import (
+	"bufio"
+	"fmt"
+	"log"
+	"math"
+	"os"
+	"strconv"
+	"strings"
+)
+
+func main() {
+	inp := StdinToStrings()
+	part1(inp)
+	part2(inp)
+}
+
+func part1(inp []string) {
+	fmt.Println("= Part 1 =")
+	var chk int
+	for i := range inp {
+		cells := strings.Split(inp[i], "\t")
+		max, min := -1, -1
+		for j := range cells {
+			tst := Atoi(cells[j])
+			if tst > max {
+				max = tst
+			}
+			if min < 0 || tst < min {
+				min = tst
+			}
+		}
+		chk += (max - min)
+	}
+	fmt.Println("Checksum: ", chk)
+	fmt.Println("")
+}
+
+func part2(inp []string) {
+	fmt.Println("= Part 2 =")
+	var chk int
+	for i := range inp {
+		cells := strings.Split(inp[i], "\t")
+		var foundIt bool
+		for j := range cells {
+			for k := j; k < len(cells); k++ {
+				jVal, kVal := Atoi(cells[j]), Atoi(cells[k])
+				if isThePair(jVal, kVal) {
+					foundIt = true
+					chk += getResult(jVal, kVal)
+					break
+				}
+			}
+			if foundIt {
+				break
+			}
+		}
+	}
+	fmt.Println("Checksum: ", chk)
+	fmt.Println("")
+}
+
+func isThePair(k, j int) bool {
+	if k == j {
+		return false
+	}
+	jVal, kVal := float64(j), float64(k)
+	return math.Mod(jVal, kVal) == 0 || math.Mod(kVal, jVal) == 0
+}
+
+func getResult(k, j int) int {
+	if k > j {
+		return k / j
+	}
+	return j / k
+}
+
+func StdinToStrings() []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
+}

2017/day02/input

@@ -0,0 +1,16 @@
+790	99	345	1080	32	143	1085	984	553	98	123	97	197	886	125	947
+302	463	59	58	55	87	508	54	472	63	469	419	424	331	337	72
+899	962	77	1127	62	530	78	880	129	1014	93	148	239	288	357	424
+2417	2755	254	3886	5336	3655	5798	3273	5016	178	270	6511	223	5391	1342	2377
+68	3002	3307	166	275	1989	1611	364	157	144	3771	1267	3188	3149	156	3454
+1088	1261	21	1063	1173	278	1164	207	237	1230	1185	431	232	660	195	1246
+49	1100	136	1491	647	1486	112	1278	53	1564	1147	1068	809	1638	138	117
+158	3216	1972	2646	3181	785	2937	365	611	1977	1199	2972	201	2432	186	160
+244	86	61	38	58	71	243	52	245	264	209	265	308	80	126	129
+1317	792	74	111	1721	252	1082	1881	1349	94	891	1458	331	1691	89	1724
+3798	202	3140	3468	1486	2073	3872	3190	3481	3760	2876	182	2772	226	3753	188
+2272	6876	6759	218	272	4095	4712	6244	4889	2037	234	223	6858	3499	2358	439
+792	230	886	824	762	895	99	799	94	110	747	635	91	406	89	157
+2074	237	1668	1961	170	2292	2079	1371	1909	221	2039	1022	193	2195	1395	2123
+8447	203	1806	6777	278	2850	1232	6369	398	235	212	992	7520	7304	7852	520
+3928	107	3406	123	2111	2749	223	125	134	146	3875	1357	508	1534	4002	4417

2017/day02/problem

@@ -0,0 +1,88 @@
+Advent of Code
+
+--- Day 2: Corruption Checksum ---
+
+   As you walk through the door, a glowing humanoid shape yells in your
+   direction. "You there! Your state appears to be idle. Come help us repair the
+   corruption in this spreadsheet - if we take another millisecond, we'll have
+   to display an hourglass cursor!"
+
+   The spreadsheet consists of rows of apparently-random numbers. To make sure
+   the recovery process is on the right track, they need you to calculate the
+   spreadsheet's checksum. For each row, determine the difference between the
+   largest value and the smallest value; the checksum is the sum of all of these
+   differences.
+
+   For example, given the following spreadsheet:
+
+ 5 1 9 5
+ 7 5 3
+ 2 4 6 8
+
+     * The first row's largest and smallest values are 9 and 1, and their
+       difference is 8.
+     * The second row's largest and smallest values are 7 and 3, and their
+       difference is 4.
+     * The third row's difference is 6.
+
+   In this example, the spreadsheet's checksum would be 8 + 4 + 6 = 18.
+
+   What is the checksum for the spreadsheet in your puzzle input?
+
+   Your puzzle answer was ____.
+
+   The first half of this puzzle is complete! It provides one gold star: *
+
+--- Part Two ---
+
+   "Great work; looks like we're on the right track after all. Here's a star for
+   your effort." However, the program seems a little worried. Can programs be
+   worried?
+
+   "Based on what we're seeing, it looks like all the User wanted is some
+   information about the evenly divisible values in the spreadsheet.
+   Unfortunately, none of us are equipped for that kind of calculation - most of
+   us specialize in bitwise operations."
+
+   It sounds like the goal is to find the only two numbers in each row where one
+   evenly divides the other - that is, where the result of the division
+   operation is a whole number. They would like you to find those numbers on
+   each line, divide them, and add up each line's result.
+
+   For example, given the following spreadsheet:
+
+ 5 9 2 8
+ 9 4 7 3
+ 3 8 6 5
+
+     * In the first row, the only two numbers that evenly divide are 8 and 2;
+       the result of this division is 4.
+     * In the second row, the two numbers are 9 and 3; the result is 3.
+     * In the third row, the result is 2.
+
+   In this example, the sum of the results would be 4 + 3 + 2 = 9.
+
+   What is the sum of each row's result in your puzzle input?
+
+   Although it hasn't changed, you can still get your puzzle input.
+
+   Answer: _____________________
+
+   You can also [Shareon Twitter Google+ Reddit] this puzzle.
+
+References
+
+   Visible links
+   . http://adventofcode.com/
+   . http://adventofcode.com/2017/about
+   . http://adventofcode.com/2017/support
+   . http://adventofcode.com/2017/events
+   . http://adventofcode.com/2017/settings
+   . http://adventofcode.com/2017/auth/logout
+   . http://adventofcode.com/2017
+   . http://adventofcode.com/2017
+   . http://adventofcode.com/2017/leaderboard
+   . http://adventofcode.com/2017/stats
+   . http://adventofcode.com/2017/sponsors
+   . http://adventofcode.com/2017/sponsors
+   . http://adventofcode.com/2017/day/2/input