Intuit interview questions

1st round : it was a system design question and it was very simple though, then i was asked about acid properties and other dbms questions, then oops four pillars . What is fully encapsulated class . After all this one dsa question and it was related to the string (string anagram) . Then i was informed i qualified this roung Round 2: i was asked to design an elevator though i took more time then expected , then they switched to another dsa question if i climb a stair and i could climb one or two steps at a time then min number of steps i could reach the top , i told tabulation recursive and memoization method but they wanted some mathematical approach