go: add «1190. Reverse Substrings Between Each Pair of Parentheses»

Signed-off-by: Matej Focko <me@mfocko.xyz>

go/reverse-substrings-between-each-pair-of-parentheses.go

@@ -0,0 +1,36 @@
+package main
+
+func reverseParentheses(s string) string {
+	getParentheses := func() []int {
+		pairing := make([]int, len(s))
+
+		opened := make([]int, 0, len(s)/2)
+		for i, c := range s {
+			if c == '(' {
+				opened = append(opened, i)
+			} else if c == ')' {
+				var j int
+				j, opened = opened[len(opened)-1], opened[:len(opened)-1]
+
+				pairing[i] = j
+				pairing[j] = i
+			}
+		}
+
+		return pairing
+	}
+
+	pairing := getParentheses()
+
+	result := make([]byte, 0, len(s))
+	for i, d := 0, 1; i < len(s); i += d {
+		if s[i] == '(' || s[i] == ')' {
+			i = pairing[i]
+			d *= -1
+		} else {
+			result = append(result, s[i])
+		}
+	}
+
+	return string(result)
+}