init

25/05/2131.go

@@ -0,0 +1,40 @@
+package main
+
+func Reverse(s string) string {
+	bytes := []byte(s) // 直接转为字节切片
+	for i, j := 0, len(bytes)-1; i < j; i, j = i+1, j-1 {
+		bytes[i], bytes[j] = bytes[j], bytes[i] // 交换字节
+	}
+	return string(bytes)
+}
+
+func longestPalindrome(words []string) int {
+	m := make(map[string]int)
+	res, center := 0, 0
+	for _, word := range words {
+		m[word]++
+	}
+	for word := range m {
+		if m[word] == 0 {
+			continue
+		}
+
+		reversed := Reverse(word)
+
+		if reversed == word {
+			pairs := m[word] / 2
+			res += pairs * 2 * 2
+			if m[word]%2 == 1 {
+				center = 2
+			}
+		} else {
+			if m[reversed] >= 1 {
+				pairs := min(m[word], m[reversed])
+				res += pairs * 4
+				m[word] -= pairs
+				m[reversed] -= pairs
+			}
+		}
+	}
+	return res + center
+}