finished no.10

hard/10.go

@@ -0,0 +1,55 @@
+package main
+
+import "fmt"
+
+func isMatch(s string, p string) bool {
+	// If former x chars of string matches former y chars
+	// of pattern, match[x][y] == true, else == false
+	var match [][]bool
+	// Init match
+	for i := 0; i < len(s)+1; i++ {
+		row := make([]bool, len(p)+1)
+		match = append(match, row)
+	}
+	// "" matches ""
+	match[0][0] = true
+	// Current & last char rank of pattern
+	currP, lastP := 1, 0
+	for currP <= len(p) {
+		zeroOrMore := false
+		// Current char of pattern
+		charP := p[currP-1]
+		if currP < len(p) && p[currP] == '*' {
+			zeroOrMore = true
+			currP++                           // To skip '*'
+			match[0][currP] = match[0][lastP] // .* pattern can match len 0 string
+		}
+		// Start from the first char of string
+		for currS := 1; currS <= len(s); currS++ {
+			charS := s[currS-1]
+			if !zeroOrMore {
+				// s1s2...sx ~ p1p2...py <=> s1...s(x-1) ~ p1...p(x-1) && sx ~ py
+				match[currS][currP] = match[currS-1][lastP] &&
+					(charP == '.' || charS == charP)
+			} else {
+				// ... <=> s1...sx ~ p1...p(y-1) [ie. py matches nothing] ||
+				// (sx ~ sy && s1...s(x-1) ~ p1...py)
+				match[currS][currP] = match[currS][lastP] ||
+					((charP == '.' || charS == charP) &&
+						match[currS-1][currP])
+			}
+		}
+		lastP = currP
+		currP++
+	}
+	return match[len(s)][len(p)]
+}
+
+func main() {
+	fmt.Println(isMatch("", ""))
+	fmt.Println(isMatch("ssssss", "p"))
+	fmt.Println(isMatch("ssssss", "s*"))
+	fmt.Println(isMatch("ssssss", "s.*s"))
+	fmt.Println(isMatch("ss", "s.*ss"))
+	fmt.Println(isMatch("ss", "s*"))
+}

hard/32.go

@@ -1,9 +1,5 @@
 package main
 
-import (
-	"fmt"
-)
-
 // 穷举
 func longestValidParenthesesOld(s string) int {
 	pair := 0
@@ -60,8 +56,8 @@ func longestValidParentheses(s string) int {
 	return max
 }
 
-func main() {
-	fmt.Println(longestValidParentheses("("))
-	fmt.Println(longestValidParentheses("()()("))
-	fmt.Println(longestValidParentheses("()(((()(()(((()(()())))(()"))
-}
+// func main() {
+// 	fmt.Println(longestValidParentheses("("))
+// 	fmt.Println(longestValidParentheses("()()("))
+// 	fmt.Println(longestValidParentheses("()(((()(()(((()(()())))(()"))
+// }