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 C (judge verdict: Accepted)

#include<stdio.h>
int dp[1001][1001];
char s[1001],t[1001];
int ans,x,y;
int max(int a,int b){
  if(a>b)return a;
  else return b;
}
int main(){
  int i,j;
  scanf("%d",&x);
  for(y=0;y<x;y++){
    scanf("%s %s",s,t);
    for(i=0;i<=1000;i++)
      for(j=0;j<=1000;j++)
	dp[i][j]=0;
    ans=0;
    for(i=1;s[i-1]!='\0';i++){
      for(j=1;t[j-1]!='\0';j++){
	if(s[i-1]==t[j-1])dp[i][j]=dp[i-1][j-1]+1;
	else dp[i][j]=max(dp[i-1][j],dp[i][j-1]);
      }
    }
    printf("%d\n",dp[i-1][j-1]);
  }
  return 0;
}