Solution Review: Problem Challenge 3

Smallest Window containing Substring (hard)

Given a string and a pattern, find the smallest substring in the given string which has all the character occurrences of the given pattern.

Example 1:

Input: String="aabdec", Pattern="abc"
Output: "abdec"
Explanation: The smallest substring having all characters of the pattern is "abdec"

Example 2:

Input: String="aabdec", Pattern="abac"
Output: "aabdec"
Explanation: The smallest substring having all character occurrences of the pattern is "aabdec"

Example 3:

Input: String="abdbca", Pattern="abc"
Output: "bca"
Explanation: The smallest substring having all characters of the pattern is "bca".

Example 4:

Input: String="adcad", Pattern="abc"
Output:

...