Go: package main

/*
最長共通部分列
*/

import (
	"bufio"
	"bytes"
	"fmt"
	"log"
	"os"
	"strconv"
	"strings"
)

func larger(l, r int) int {
	if l > r {
		return l
	}
	return r
}

var memo [1001][1001]int

func countLCS(x, y string) int {
	x = " " + x
	y = " " + y
	max := 0
	for xi := 1; xi < len(x); xi++ {
		for yi := 1; yi < len(y); yi++ {
			if x[xi] == y[yi] {
				memo[xi][yi] = memo[xi-1][yi-1] + 1
			} else {
				memo[xi][yi] = larger(memo[xi-1][yi], memo[xi][yi-1])
			}
			max = larger(max, memo[xi][yi])
		}
	}
	return max
}

func main() {
	scanner := makeScanner(1024)
	q := eGetInt(scanner)
	for i := 0; i < q; i++ {
		x := eGetLine(scanner)
		y := eGetLine(scanner)
		fmt.Println(countLCS(x, y))
	}
}

////////////////////////////////////////////////////////////////////////////////
// ライブラリ
////////////////////////////////////////////////////////////////////////////////
func makeScanner(maxByte int) *bufio.Scanner {
	scanner := bufio.NewScanner(os.Stdin)
	scanner.Buffer(make([]uint8, 0, 8192), maxByte)
	return scanner
}
func makeWordScanner() *bufio.Scanner {
	scanner := makeScanner(8192)
	scanner.Split(bufio.ScanWords)
	return scanner
}
func eGetLine(r *bufio.Scanner) string {
	if r.Scan() {
		return r.Text()
	}
	err := r.Err()
	if err != nil {
		log.Fatal(err)
	}
	// EOF
	return ""
}
func eGetInt(r *bufio.Scanner) int {
	line := eGetLine(r)
	return eAtoi(line)
}
func eGetFields(r *bufio.Scanner) []string {
	line := eGetLine(r)
	return strings.Fields(line)
}
func eGetInts(r *bufio.Scanner) []int {
	fields := eGetFields(r)
	ints := make([]int, len(fields))
	for i := 0; i < len(ints); i++ {
		ints[i] = eAtoi(fields[i])
	}
	return ints
}
func eGetChars(r *bufio.Scanner) []string {
	line := eGetLine(r)
	return strings.Split(line, "")
}
func eAtoi(s string) int {
	n, err := strconv.Atoi(s)
	if err != nil {
		log.Fatal(err)
	}
	return n
}

type ints []int

func (s ints) String() string {
	var buf bytes.Buffer
	buf.WriteString("[")
	sep := ""
	for _, v := range s {
		buf.WriteString(fmt.Sprintf("%s%d", sep, v))
		sep = ", "
	}
	buf.WriteString("]")
	return buf.String()
}

func reverse(a ints) ints {
	r := make(ints, len(a))
	for i := 0; i < len(a); i++ {
		r[i] = a[len(a)-1-i]
	}
	return r
}
func max(a ints) (int, bool) {
	if len(a) == 0 {
		return 0, false
	}
	m := a[0]
	for _, e := range a {
		if e > m {
			m = e
		}
	}
	return m, true
}
func min(a []int) int {
	m := a[0]
	for _, v := range a {
		if v < m {
			m = v
		}
	}
	return m
}

func sum(a ints) int {
	if len(a) == 0 {
		return 0
	}
	sum := 0
	for _, e := range a {
		sum += e
	}
	return sum
}
func find(n int, a ints) int {
	for i, v := range a {
		if n == v {
			return i
		}
	}
	return -1
}

Python: n=int(input())
ans=[]
for k in range(n):
    s1=input()
    s2=input()
    dp=[[0 for i in range(len(s2)+1)] for j in range(len(s1)+1)]
    for i in range(1,len(s1)+1):
        for j in range(1,len(s2)+1):
            if s1[i-1]==s2[j-1]:
                dp[i][j]=dp[i-1][j-1]+1
            else:
                dp[i][j]=max(dp[i-1][j],dp[i][j-1])


    ans.append(dp[len(s1+1)][len(s2+1)])
for a in ans:
    print(a)

Python: for _ in[0]*int(input()):
 X,Y,z=input(),input(),[]
 for y in Y:
  s=0
  for i,k in enumerate(z):
   t=X.find(y,s)+1
   if t<1:break
   if t<k:z[i]=t
   s=k
  else:
   t=X.find(y,s)+1
   if t:z+=[t]
 print(len(z))

Python: from sys import stdin
def lcs(x, y):
    m = len(x)
    n = len(y)
    c = [[0]*(m + 2) for a in range(n + 2)]
    for i in range(1, m + 1):
        for j in range(1, n + 1):
            if x[i-1] == y[j-1]:
                c[i][j] = (c[i - 1][j - 1]) + 1
            else:
                c[i][j] = max(c[i - 1][j], c[i][j - 1])
    return max(max(c))

n = int(input().rstrip())
strs = stdin.readlines()
ret = []
for i in range(n):
    # s1 = strs[i*2].rstrip()
    # s2 = strs[i*2+1].rstrip()
    ret.append(lcs(strs[i*2].rstrip(), strs[i*2+1].rstrip()))
print(*ret, sep="\n")

Python: def lcs(X, Y):
    row, colums = len(X) + 1, len(Y) + 1
    lcs_list = [[0 for y in range(colums)] for x in range(row)]
    for i in range(row):
        for j in range(colums):
            if i == 0 or j == 0:
                lcs_list[i][j] = 0
            elif X[i-1] == Y[j-1]:
                lcs_list[i][j] = lcs_list[i-1][j-1] + 1
            else:
                lcs_list[i][j] = max(lcs_list[i][j-1], lcs_list[i-1][j])
    return lcs_list[-1][-1]

import sys
n = int(input())
input_lines = sys.stdin.readlines()
for i in range(n):
    X = list(input_lines[2*i].rstrip())
    Y = list(input_lines[2*i+1].rstrip())
    print(lcs(X,Y))

Python: import sys


def len_lcs(s1, s2):
    """Find length of the longest common sequence(LCS) of strings s1 and s2.
    The complexity is ~MN.

    >>> len_lcs("abc", "abc")
    3
    >>> len_lcs("abcbdaba", "bdcaba")
    5
    """
    results = [0] * len(s1)

    for i, c2 in enumerate(s2):
        sec1, pr1 = 0, 0
        for j, c1 in enumerate(s1):
            if c1 == c2:
                match = 1
            else:
                match = 0
            pr2 = results[j]
            mval = max(sec1, pr2, pr1 + match)
            results[j] = mval
            sec1, pr1 = mval, pr2

    return results[-1]


def run():
    n = int(input())
    s = []
    for line in sys.stdin:
        s.append(line.strip())
    for i in range(0, 2*n, 2):
        print(len_lcs(s[i], s[i+1]))


run()

Python: m = int(input())
for i in range(m):
    str1 = input()
    str2 = input()
    A = [0 for j in range(len(str2)+1)]
    for j in range(len(str1)):
        for k in range(len(str2)):
            if(str1[j]==str2[k]):
                A[k+1] = A[k+1]+1
            else:
                if(A[k] > A[k+1]):
                    A[k+1] = A[k]
    print(A[-1])

Python: def length_of_lcs(x, y):
    n = len(y)
    #pre_row = [0] * (n + 1)
    cur_row = [0] * (n + 1)
    for x_c in x:
        prev_row = cur_row[:]
        for j, y_c in enumerate(y):
            if x_c == y_c:
                cur_row[j+1] = prev_row[j] + 1
            elif cur_row[j] > cur_row[j+1]:
                cur_row[j+1] = cur_row[j]

    return cur_row[n]


if __name__ == '__main__':
    N = int(input())
    for _ in range(N):
        x = input()
        y = input()
        print(length_of_lcs(x, y))

Python: def lcs(X, Y):
    dp = []
    for y in Y:
        bgn_idx = 0
        for i, cur_idx in enumerate(dp):
            chr_idx = X.find(y, bgn_idx) + 1
            
            if not chr_idx:
                break
            dp[i] = min(cur_idx, chr_idx)
            bgn_idx = cur_idx
        else:
            chr_idx = X.find(y, bgn_idx) + 1
            if chr_idx:
                dp.append(chr_idx)
    return len(dp)

q = int(input())
for i in range(q):
    X = input()
    Y = input()
    print(lcs(X, Y))

Python: import sys
sys.setrecursionlimit(10000)

def calc(x,y):
    i = len(x)
    j = len(y)
    if not d[i][j] == None:
        return d[i][j]
    else:
        if x[-1] == y[-1]:
            tmp = max(calc(x[:-1],y[:-1])+1,calc(x[:-1],y),calc(x,y[:-1]))
            d[i][j] = tmp
            return tmp
        else:
            tmp = max(calc(x[:-1],y),calc(x,y[:-1]))
            d[i][j] = tmp
            return tmp
        
q = int(input())
for i in range(q):
    x = input()
    y = input()
    d = [[0 if i == 0 or j == 0 else None for i in range(len(y)+1)] for j in range(len(x)+1)]
    print(calc(x,y))

Python: # -*- coding: utf-8 -*-
"""
Created on Fri May  4 20:33:37 2018
ALDS1_10_C
@author: maezawa
"""

def longest(x, y):
    m = len(x)
    n = len(y)
    c = [[0 for _ in range(n+1)] for _ in range(m+1)]
    for i in range(m):
        for j in range(n):
            #print(i,j)
            if x[i] == y[j]:
                c[i][j] = c[i-1][j-1] + 1
            else:
                c[i][j] = max(c[i-1][j], c[i][j-1])
    return c[m-1][n-1]

q = int(input())
for i in range(q):
    x = input()
    y = input()
    print(longest(x, y))