Problem:
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Longest Common Subsequence

For given two sequences $X$ and $Y$, a sequence $Z$ is a common subsequence of $X$ and $Y$ if $Z$ is a subsequence of both $X$ and $Y$. For example, if $X = \{a,b,c,b,d,a,b\}$ and $Y = \{b,d,c,a,b,a\}$, the sequence $\{b,c,a\}$ is a common subsequence of both $X$ and $Y$. On the other hand, the sequence $\{b,c,a\}$ is not a longest common subsequence (LCS) of $X$ and $Y$, since it has length 3 and the sequence $\{b,c,b,a\}$, which is also common to both $X$ and $Y$, has length 4. The sequence $\{b,c,b,a\}$ is an LCS of $X$ and $Y$, since there is no common subsequence of length 5 or greater.

Write a program which finds the length of LCS of given two sequences $X$ and $Y$. The sequence consists of alphabetical characters.

Input

The input consists of multiple datasets. In the first line, an integer $q$ which is the number of datasets is given. In the following $2 \times q$ lines, each dataset which consists of the two sequences $X$ and $Y$ are given.

Output

For each dataset, print the length of LCS of $X$ and $Y$ in a line.

Constraints

$1 \leq q \leq 150$

$1 \leq$ length of $X$ and $Y$ $\leq 1,000$

$q \leq 20$ if the dataset includes a sequence whose length is more than 100

Sample Input 1

3
abcbdab
bdcaba
abc
abc
abc
bc

Sample Output 1

4
3
2

Reference

Introduction to Algorithms, Thomas H. Cormen, Charles E. Leiserson, Ronald L. Rivest, and Clifford Stein. The MIT Press.

Solution in JAVA (judge verdict: Wrong Answer)

import java.io.*;
import java.util.*;
import java.util.stream.Collectors;
import java.util.stream.IntStream;
class Main{
    public void run(){
        try(BufferedReader br = new BufferedReader(new InputStreamReader(System.in))){
            int term = Integer.parseInt(br.readLine());
            for(int i = 0;i < term;i++){
                String a = br.readLine();
                String b = br.readLine();
                lcs(a, b);
            }
        }catch(Exception e){
        }
    }

    public void lcs(String a, String b){
        int aLength = a.length();
        int bLength = b.length();
        String[] aArray = a.split("");
        String[] bArray = b.split("");
        Integer[][] strMap = new Integer[1000][1000];

        for(int i = 0;i <= aLength; i++){
            strMap[i][0] = 0;
        }
        for(int j = 0; j <= aLength; j++){
            strMap[0][j] = 0;
        }

        int maxLCS = 0;

        for(int i = 1;i <= aLength; i++){
            for(int j = 1; j <= bLength; j++){
                if(Objects.equals(aArray[i - 1], bArray[j - 1])){
                    strMap[i][j] = strMap[i-1][j-1] + 1;
                }
                else
                    strMap[i][j] = Math.max(strMap[i-1][j],strMap[i][j-1]);
                maxLCS = Math.max(maxLCS, strMap[i][j]);
            }
        }
        System.out.println(strMap[aLength][bLength]);
    }

    public static void main(String[] args){
        new Main().run();
    }
}