Medlife.com Software Development Engineer interview questions

1st Round: 3 coding questions moderate level (time =2 hours)..dont remember the questions exactly ..one of them was based on stack(next greater and next smaller type question) and other one was on dfs/bfs. ones who solved one question got into 2nd round. 14/180 qualified for 2nd round. 2nd round: It was interview face to face. He asked me 3 coding questions.. 1: given a knight and a position on chessboard..will knight reach that position ever? 2:given some playing cards one of them is missing..you have to find which one is missing 3: dont remember exactly i answered all of them 3rd round: 3 coding questions: 1: given an array of 1's and 0 's find maximum subarray length whose no of 1's==no of 0's 2:you have very large strings and there is stream of them you have to find if it has come before or not? 3:dont remember exactly