From 967ca0f1a233ed2c858a994fcb712618362144d2 Mon Sep 17 00:00:00 2001
From: Matej Focko <me@mfocko.xyz>
Date: Sun, 15 Sep 2024 17:55:26 +0200
Subject: [PATCH] =?UTF-8?q?go:=20add=20=C2=AB1371.=20Find=20the=20Longest?=
 =?UTF-8?q?=20Substring=20Containing=20Vowels=20in=20Even=20Counts=C2=BB?=
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Signed-off-by: Matej Focko <me@mfocko.xyz>
---
 ...string-containing-vowels-in-even-counts.go | 40 +++++++++++++++++++
 1 file changed, 40 insertions(+)
 create mode 100644 go/find-the-longest-substring-containing-vowels-in-even-counts.go

diff --git a/go/find-the-longest-substring-containing-vowels-in-even-counts.go b/go/find-the-longest-substring-containing-vowels-in-even-counts.go
new file mode 100644
index 0000000..d2dda97
--- /dev/null
+++ b/go/find-the-longest-substring-containing-vowels-in-even-counts.go
@@ -0,0 +1,40 @@
+package main
+
+func findTheLongestSubstring(s string) int {
+	getMask := func(c rune) int {
+		switch c {
+		case 'a':
+			return 1
+		case 'e':
+			return 2
+		case 'i':
+			return 4
+		case 'o':
+			return 8
+		case 'u':
+			return 16
+		default:
+			return 0
+		}
+	}
+
+	longest := 0
+
+	indices := make([]int, 32)
+	for i, _ := range indices {
+		indices[i] = -1
+	}
+
+	xor := 0
+	for i, c := range s {
+		xor ^= getMask(c)
+
+		if indices[xor] == -1 && xor != 0 {
+			indices[xor] = i
+		}
+
+		longest = max(longest, i-indices[xor])
+	}
+
+	return longest
+}