https://leetcode.com/problems/longest-palindromic-substring\n\nI saw a [solution](https://leetcode.com/problems/longest-palindromic-substring/discuss/2921/Share-my-Java-solution-using-dynamic-programming) with 1-d dp.\n\n![image](https://assets.leetcode.com/users/kenpeter/image_1558939606.png)\n\n* Are you able to explain what is each column in 1d array tracking? \n* Why j-i<2? Should it be j-i<3. i.e. a; aa; aaa 3. \n* I ran the code on paper. I can see that each column is refreshing in each iteration. Are you able to explain what is happen to the array in 1 iternation?\n

https://leetcode.com/problems/longest-palindromic-substring\n\nI saw a solution with 1-d dp.\n\n\n\n Are you able to explain what is each column in 1d array tra