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.