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>
#include<string.h>
#define N 1001
static const int S=1000;

int longest(char *A,char *B);

int main()
{
  int n,i;
  char A[N],B[N];

  scanf("%d",&n);

  for(i=0; i<n; i++){
    scanf("%s%s",A,B);
    printf("%d\n",longest(A,B));
  }

  return 0;
}

int longest(char *A,char *B)
{
  int i,j,C[S+1][S+1],p,q;

  p=strlen(A);
  q=strlen(B);

  for(i=0; i<=p; i++)C[i][0]=0;
  for(j=1; j<=q; j++)C[0][j]=0;

  for(i=0; i<=p; i++){
    for(j=1; j<=q; j++){
      
      if(A[i-1]==B[j-1])C[i][j]=C[i-1][j-1]+1;
      
      else if(C[i-1][j-1]>=C[i][j-1])C[i][j]=C[i-1][j];
      
      else C[i][j]=C[i][j-1];
    }
  }
  if(i==0 || j==0)return 0;
  else if(p==q)return C[i-1][j-1];
  else if(p!=q)return C[p][q];
  return 0;
}