LeetCode 87. 扰乱字符串

class Solution {
public:
    bool isScramble(string s1, string s2) {
        int n=s1.size();
       vector>> f(n,vector>(n,vector(n+1)));

       for(int k=1;k<=n;k++){
           for(int i=0;i+k<=n;i++){
               for(int j=0;j+k<=n;j++){
                   if(k==1){
                       if(s1[i]==s2[j]) f[i][j][k]=true;
                   }else{
                       for(int u=1;u