From 561b10916db66e1a3da47cd50a416d2f59e37667 Mon Sep 17 00:00:00 2001
From: David Ashby <delta.mu.alpha@gmail.com>
Date: Sun, 3 Dec 2023 20:57:52 -0500
Subject: [PATCH] a little more refactoring

---
 03/main.go | 66 +++++++++++++++++++++---------------------------------
 1 file changed, 26 insertions(+), 40 deletions(-)

diff --git a/03/main.go b/03/main.go
index 6b7f0fc..1af0794 100644
--- a/03/main.go
+++ b/03/main.go
@@ -45,8 +45,8 @@ type coord struct {
 	col int
 }
 
-func isSymbol(s schematic, row, col int) bool {
-	if c, ok := s[coord{row, col}]; ok {
+func isSymbol(s schematic, c coord) bool {
+	if c, ok := s[c]; ok {
 		return c.symb != 0
 	}
 	return false
@@ -87,20 +87,13 @@ func partOne() {
 		for col := 0; col <= 139; col++ {
 			if entry, ok := schematic[coord{row, col}]; ok && entry.symb == 0 {
 				part := mustAtoi(entry.num)
-				if isSymbol(schematic, row, col-1) {
-					// look behind
-					sum += part
-				}
-				if isSymbol(schematic, row, col+len(entry.num)) {
-					// look ahead
+				if isSymbol(schematic, coord{row, col - 1}) || isSymbol(schematic, coord{row, col + len(entry.num)}) {
+					// look ahead and look behind
 					sum += part
 				}
 				for i := -1; i < len(entry.num)+1; i++ {
 					// check row above and below
-					if isSymbol(schematic, row-1, col+i) {
-						sum += part
-					}
-					if isSymbol(schematic, row+1, col+i) {
+					if isSymbol(schematic, coord{row - 1, col + i}) || isSymbol(schematic, coord{row + 1, col + i}) {
 						sum += part
 					}
 				}
@@ -149,38 +142,31 @@ func partTwo() {
 			if entry, ok := schematic[coord{row, col}]; ok && entry.symb == 0 {
 				offset := len(entry.num)
 				part := mustAtoi(entry.num)
-				if isSymbol(schematic, row, col-1) {
-					k := coord{row, col - 1}
-					if gears[k] != 0 {
-						sum += gears[k] * part
-					} else {
-						gears[k] = part
-					}
+				found := false
+				k := coord{}
+				if isSymbol(schematic, coord{row, col - 1}) {
+					k = coord{row, col - 1}
+					found = true
 				}
-				if isSymbol(schematic, row, col+offset) {
-					k := coord{row, col + offset}
-					if gears[k] != 0 {
-						sum += gears[k] * part
-					} else {
-						gears[k] = part
-					}
+				if isSymbol(schematic, coord{row, col + offset}) {
+					k = coord{row, col + offset}
+					found = true
 				}
 				for i := -1; i < offset+1; i++ {
-					if isSymbol(schematic, row-1, col+i) {
-						k := coord{row - 1, col + i}
-						if gears[k] != 0 {
-							sum += gears[k] * part
-						} else {
-							gears[k] = part
-						}
+					if isSymbol(schematic, coord{row - 1, col + i}) {
+						k = coord{row - 1, col + i}
+						found = true
 					}
-					if isSymbol(schematic, row+1, col+i) {
-						k := coord{row + 1, col + i}
-						if gears[k] != 0 {
-							sum += gears[k] * part
-						} else {
-							gears[k] = part
-						}
+					if isSymbol(schematic, coord{row + 1, col + i}) {
+						k = coord{row + 1, col + i}
+						found = true
+					}
+				}
+				if found {
+					if gears[k] == 0 {
+						gears[k] = part
+					} else {
+						sum += gears[k] * part
 					}
 				}
 			}