package top100liked

import (
	"fmt"
	"testing"
)

// https://leetcode.cn/problems/palindrome-partitioning/description/?envType=study-plan-v2&envId=top-100-liked

func partition(s string) [][]string {
	res := [][]string{}
	path := []string{}
	// 动态规划，降低查找回文串的时间复杂度
	dp := make([][]bool, len(s))
	for i := range len(s) {
		dp[i] = make([]bool, len(s))
		dp[i][i] = true
	}
	for length := 2; length <= len(s); length++ {
		for i := 0; i+length <= len(s); i++ {
			j := i + length - 1
			dp[i][j] = (s[i] == s[j]) && (length <= 2 || dp[i+1][j-1])
		}
	}

	var helper func(start int)
	helper = func(start int) {
		if start == len(s) {
			cp := make([]string, len(path))
			copy(cp, path)
			res = append(res, cp)
			return
		}
		for end := start; end < len(s); end++ {
			if dp[start][end] {
				path = append(path, s[start:end+1])
				helper(end + 1)
				path = path[:len(path)-1]
			}
		}
	}

	helper(0)

	return res
}

func Test(t *testing.T) {
	fmt.Printf("%+v\n", partition("aab"))
}

func Test2(t *testing.T) {
	fmt.Printf("%+v\n", partition("a"))
}