A recently summarized universal violent cracking method

Universal brute force solution

I've written a lot of questions recently , I'm glad I can write notes by blogging , This is convenient for me to review constantly in the future . I've had a whim recently , Because many problems are converted into arrays for operation . For example, some problems of string , We often see .toCharArray()String[] Some of the code for , Directly convert a string group into a string array , It shows that string array is very important for solving string problems .
that , Is there a universal violent cracking method that can solve some problems in the array ( such as ： The problem of finding the longest common substring , The longest string length problem and so on ). Now I summarize my thoughts ：

// First convert a string into a character array , Let's say the array is nums
for(int i=0; i<nums.length; i++