From 9057173ca5878fac523c769e105d64e1aa614531 Mon Sep 17 00:00:00 2001
From: eriedaberrie <eriedaberrie@gmail.com>
Date: Mon, 4 Dec 2023 11:46:32 -0800
Subject: [PATCH] 2023 day 4: remove goto and replace vector with set

Due to popular demand
---
 2023/4/main-1.cpp | 17 ++++++++---------
 2023/4/main-2.cpp | 41 ++++++++++++++++++-----------------------
 2 files changed, 26 insertions(+), 32 deletions(-)

diff --git a/2023/4/main-1.cpp b/2023/4/main-1.cpp
index 246ae46..7e09906 100644
--- a/2023/4/main-1.cpp
+++ b/2023/4/main-1.cpp
@@ -15,18 +15,17 @@ int main() {
 		string left = line.substr(start + 2, bar - start - 3);
 		string right = line.substr(bar + 2);
 		istringstream lss(left), rss(right);
-		vector<int> rv;
-		while (!rss.eof()) {
-			int n;
-			rss >> n;
-			rv.push_back(n);
-		}
+		set<int> ls;
 		while (!lss.eof()) {
 			int n;
 			lss >> n;
-			for (auto no : rv) {
-				if (no == n)
-					count <<= 1;
+			ls.insert(n);
+		}
+		while (!rss.eof()) {
+			int n;
+			rss >> n;
+			if (ls.find(n) != ls.end()) {
+				count <<= 1;
 			}
 		}
 		ret += count >> 1;
diff --git a/2023/4/main-2.cpp b/2023/4/main-2.cpp
index 9d35fc8..9dc19a1 100644
--- a/2023/4/main-2.cpp
+++ b/2023/4/main-2.cpp
@@ -5,45 +5,40 @@ int main() {
 	ios::sync_with_stdio(0);
 	cin.tie(0);
 
-	int ret = 0;
-	vector<vector<int>> lefts, rights;
-	vector<int> copies;
+	vector<int> counts, copies;
 
 	string line;
 	while (getline(cin, line) && !line.empty()) {
-		copies.push_back(1);
 		int start = line.find(':');
 		int bar = line.find('|');
 		string left = line.substr(start + 2, bar - start - 3);
 		string right = line.substr(bar + 2);
 		istringstream lss(left), rss(right);
-		vector<int> rv, lv;
-		while (!rss.eof()) {
-			int n;
-			rss >> n;
-			rv.push_back(n);
-		}
-		rights.push_back(rv);
+		set<int> ls;
+		int count = 0;
 		while (!lss.eof()) {
 			int n;
 			lss >> n;
-			lv.push_back(n);
+			ls.insert(n);
 		}
-		lefts.push_back(lv);
+		while (!rss.eof()) {
+			int n;
+			rss >> n;
+			if (ls.find(n) != ls.end())
+				count++;
+		}
+		counts.push_back(count);
+		copies.push_back(1);
 	}
-	for (int cn = 0; cn < copies.size(); cn++) {
+	int ret = 0;
+	for (int cn = 0; cn < counts.size(); cn++) {
 		ret += copies[cn];
 		int n = cn;
-		for (int ln : lefts[cn]) {
-			for (int rn : rights[cn]) {
-				if (ln == rn) {
-					if (++n == copies.size())
-						goto end;
-					copies[n] += copies[cn];
-				}
-			}
+		for (int i = 0; i < counts[cn]; i++) {
+			if (++n == copies.size())
+				break;
+			copies[n] += copies[cn];
 		}
-	end:;
 	}
 	cout << ret << '\n';
 }