Leetcode: Scramble String

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 and swap its two children, it produces a scrambled string .
 is a scrambled string of .
 and , it produces a scrambled string .
 is a scrambled string of .
有一種方法叫做簡單粗暴。。。
遞迴+剪枝
bool isScramble(string s1, string s2) { // Note: The Solution object is instantiated only once. if(s1.length() != s2.length()) return false;if(s1 == s2) return true;int A[26] = {0};for(int i = 0; i < s1.length(); i++)++A[s1[i]-'a'];for(int j = 0; j < s2.length(); j++)--A[s2[j]-'a'];for(int k = 0; k < 26; k++)if(A[k] != 0) return false; for(int i = 1; i < s1.length(); i++){bool result = isScramble(s1.substr(0,i), s2.substr(0,i)) && isScramble(s1.substr(i), s2.substr(i));result = result || (isScramble(s1.substr(0,i), s2.substr(s2.length()-i, i))&& isScramble(s1.substr(i), s2.substr(0,s2.length()-i)));if(result) return true;}return false; }