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())

for i in range(n):
    a=list(input())
    b=list(input())

    r=[[0 for j in range(len(b)+1)]for i in range(len(a)+1)]

    for j in range(1,len(a)+1):
        for k in range(1,len(b)+1):
            c=max(r[j-1][k-1],r[j-1][k],r[j][k-1])
            if a[j-1]==b[k-1]:
                c=max(r[j-1][k-1]+1,r[j-1][k],r[j][k-1])
            
            r[j][k]=c
            print(r[j][k],end="")
        print(" ",end="\n")
    
    print(r[len(a)][len(b)])

Python: def calc_lcs2(X, Y):
    max_lcs = 0
    m = len(X)
    n = len(Y)
    X = ' ' + X
    Y = ' ' + Y
    c = [[0]*(m+1) for i in range(n+1)]
    for i in range(1, m+1):
        for j in range(1, n+1):
            if X[i] == Y[j]:
                c[i][j] = c[i - 1][j - 1] + 1
            elif c[i - 1][j] >= c[i][j - 1]:
                c[i][j] = c[i - 1][j]
            else:
                c[i][j] = c[i][j - 1]
    for row in c:
        max_lcs = max(row)
    return max_lcs



if __name__ == '__main__':
    # ??????????????\???
    num = int(input())
    # f = open('input.txt')
    # num = int(f.readline())

    for _ in range(num):
        X = input()
        Y = input()
        # X = f.readline().strip()
        # Y = f.readline().strip()

        # ???????????????
        result = calc_lcs2(X, Y)

        # ???????????¨???
        print(result)

Python: q = int(input())
for _ in range(q):
    x = input()
    y = input()
    m = len(x)
    n = len(y)
    c = [0] * (n + 1)
    for i in range(m):
        tmp = x[i]
        c_ = c[:]
        for j in range(n):
            if tmp == y[j]:
                c[j + 1] = c_[j] + 1
            elif c[j + 1] < c[j]:
                c[j + 1] = c[j]
    print(c[-1])

Python: def lcs_rec(i, j):
    if i == 0 or j == 0:
        return 0

    if X[i - 1] == Y[j - 1]:
        return lcs_rec(i - 1, j - 1) + 1
    else:
        return max(lcs_rec(i - 1, j), lcs_rec(i, j - 1))

q = int(input())

for i in range(q):
    X = input()
    Y = input()

    ans = lcs_rec(len(X), len(Y))

    print(ans)

Python: q = int(input())
for _ in [0]*q:
    s1, s2 = input(), input()
    l1, l2 = len(s1), len(s2)

    dp = [[0]*(l2+1) for _ in [0]*(l1+1)]
    for i, (c1, prev, cur) in enumerate(zip(s1, dp, dp[1:]), start=1):
        for j, (c2, ul, u, l, c) in enumerate(zip(s2, prev, prev[1:], cur, cur[1:]), start=1):
            dp[i][j] = max(ul+(c1==c2), u, l, c)

    print(dp[-1][-1])

Python: def lcs(X,Y):
    Xlength = len(X)
    Ylength = len(Y)

    for i in range(Xlength+1):
        c[i][0] = 0
    for i in range(Ylength+1):
        c[0][i] = 0

    for i in range(Xlength):
        for j in range(Ylength):
            if X[i] == Y[j]:
                c[i+1][j+1] = c[i][j]+1
            else:
                c[i+1][j+1] = max(c[i][j+1],c[i+1][j])

    return c[Xlength][Ylength]

    # print(X,Y)
    # if Xlength == 0 or Ylength == 0:
    #     c[Xlength][Ylength] = 0
    #     return c[Xlength][Ylength]
    #
    #
    #
    # if X[Xlength -1] == Y[Ylength -1]:
    #     if c[Xlength-1][Ylength-1] is not None:
    #         c[Xlength][Ylength] = c[Xlength-1][Ylength-1]+1
    #     else:
    #         c[Xlength][Ylength] = lcs(X[:Xlength-1], Y[:Ylength-1])+1
    # else:
    #     if c[Xlength-1][Ylength] is not None and c[Xlength][Ylength-1] is not None:
    #         c[Xlength][Ylength] = max(c[Xlength][Ylength-1],c[Xlength-1][Ylength])
    #     elif c[Xlength-1][Ylength] is not None:
    #         c[Xlength][Ylength] = max(lcs(X,Y[:Ylength-1]),c[Xlength-1][Ylength])
    #     elif c[Xlength][Ylength-1] is not None:
    #         c[Xlength][Ylength] = max(c[Xlength][Ylength-1],lcs(X[:Xlength-1],Y))
    #     else:
    #         c[Xlength][Ylength] = max(lcs(X,Y[:Ylength-1]),lcs(X[:Xlength-1],Y))
    #
    # return c[Xlength][Ylength]


n = int(input())
X = []
Y = []
c = [[None]*1001 for i in range(1001)]


for i in range(n):
    X.append(input())
    Y.append(input())

for i in range(n):
    # print(i)
    print(lcs(X[i],Y[i]))
    c = [[None]*1001 for i in range(1001)]

Python: 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 = calc(x[:-1],y[:-1])+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: q = int(input())

for k in range(q):
    x = input()
    y = input()
    lcs = [0]*(len(x)+1)
    for i in range(len(y)):
        w1 = y[i]
        lcs_2 = lcs[:]
        for j in range(len(x)):
            if x[j] == w1:
                lcs[j+1] = lcs_2[j] + 1  
            elif lcs[j+1] < lcs[j]:
                lcs[j+1] = lcs[j]
    print(lcs[-1])