We use cookies to ensure you have the best browsing experience on our website. Please read our cookie policy for more information about how we use cookies.
  1. Prepare
  2. Algorithms
  3. Strings
  4. Common Child

Common Child

A string is said to be a child of a another string if it can be formed by deleting 0 or more characters from the other string. Letters cannot be rearranged. Given two strings of equal length, what's the longest string that can be constructed such that it is a child of both?

Example


These strings have two children with maximum length 3, ABC and ABD. They can be formed by eliminating either the D or C from both strings. Return .

Function Description

Complete the commonChild function in the editor below.

commonChild has the following parameter(s):

  • string s1: a string
  • string s2: another string

Returns

  • int: the length of the longest string which is a common child of the input strings

Input Format

There are two lines, each with a string, and .

Constraints

  • where means "the length of "
  • All characters are upper case in the range ascii[A-Z].

Sample Input

HARRY
SALLY

Sample Output

 2

Explanation

The longest string that can be formed by deleting zero or more characters from and is , whose length is 2.

Sample Input 1

AA
BB

Sample Output 1

0

Explanation 1

and have no characters in common and hence the output is 0.

Sample Input 2

SHINCHAN
NOHARAAA

Sample Output 2

3

Explanation 2

The longest string that can be formed between and while maintaining the order is .

Sample Input 3

ABCDEF
FBDAMN

Sample Output 3

2

Explanation 3
is the longest child of the given strings.