Min Window Substring

Have the function MinWindowSubstring(strArr) take the array of strings stored in strArr, which will contain only two strings, the first parameter being the string N and the second parameter being a string K of some characters, and your goal is to determine the smallest substring of N that contains all the characters in K. For example: if strArr is ["aaabaaddae", "aed"] then the smallest substring of N that contains the characters a, e, and d is "dae" located at the end of the string. So for this example your program should return the string dae.

Another example: if strArr is ["aabdccdbcacd", "aad"] then the smallest substring of N that contains all of the characters in K is "aabd" which is located at the beginning of the string. Both parameters will be strings ranging in length from 1 to 50 characters and all of K's characters will exist somewhere in the string N. Both strings will only contains lowercase alphabetic characters.

Examples

Input: ["ahffaksfajeeubsne", "jefaa"]
Output: aksfaje

Input: ["aaffhkksemckelloe", "fhea"]
Output: affhkkse