give string s1 s2 size n stre evil return number good stringsA good string size n alphabetically great equal s1 alphabetically small equal s2 contain stre evil substring since answer huge number return modulo 109 7 Example 1input n 2 s1 aa s2 da evil bOutput 51 Explanation there 25 good string start aaacadaz then 25 good string start c cacccdcz finally good string start d da Example 2input n 8 s1 leetcode s2 leetgoe evil leetOutput 0 Explanation all string greater equal s1 small equal s2 start prefix leet good stringexample 3input n 2 s1 gx s2 gz evil xOutput 2 constraintss1length ns2length ns1 s21 n 5001 evillength 50All string consist lowercase english letter