Go: package main

import (
	"bufio"
	"fmt"
	"os"
	"strconv"
)

// I/O
type Scanner struct {
	sc *bufio.Scanner
}

func NewScanner() *Scanner {
	sc := bufio.NewScanner(os.Stdin)
	sc.Split(bufio.ScanWords)
	sc.Buffer(make([]byte, 1024), int(1e+9))
	return &Scanner{sc}
}

func (s *Scanner) nextStr() string {
	s.sc.Scan()
	return s.sc.Text()
}

func (s *Scanner) nextInt() int {
	i, e := strconv.Atoi(s.nextStr())
	if e != nil {
		panic(e)
	}
	return i
}

func (s *Scanner) nextFloat() float64 {
	f, e := strconv.ParseFloat(s.nextStr(), 64)
	if e != nil {
		panic(e)
	}
	return f
}

func (s *Scanner) nextRuneSlice() []rune {
	return []rune(s.nextStr())
}

func (s *Scanner) nextIntSlice(n int) []int {
	res := make([]int, n)
	for i := 0; i < n; i++ {
		res[i] = s.nextInt()
	}
	return res
}

func (s *Scanner) nextFloatSlice(n int) []float64 {
	res := make([]float64, n)
	for i := 0; i < n; i++ {
		res[i] = s.nextFloat()
	}
	return res
}

// Arithmetic
func max(nums ...int) int {
	m := nums[0]
	for _, i := range nums {
		if m < i {
			m = i
		}
	}
	return m
}

func min(nums ...int) int {
	m := nums[0]
	for _, i := range nums {
		if m > i {
			m = i
		}
	}
	return m
}

func abs(x int) int {
	if x > 0 {
		return x
	}
	return -x
}

func pow(x, y int) int {
	res := 1
	for i := 0; i < y; i++ {
		res *= x
	}
	return res
}

func ceil(a, b int) int {
	if a%b == 0 {
		return a / b
	} else {
		return a/b + 1
	}
}

// Sort
type RuneSlice []rune

func (a RuneSlice) Len() int           { return len(a) }
func (a RuneSlice) Less(i, j int) bool { return a[i] < a[j] }
func (a RuneSlice) Swap(i, j int)      { a[i], a[j] = a[j], a[i] }

// Main
func main() {
	sc := NewScanner()
	wtr := bufio.NewWriter(os.Stdout)
	Q := sc.nextInt()
	for q := 0; q < Q; q++ {
		X, Y := sc.nextStr(), sc.nextStr()
		xLen, yLen := len(X), len(Y)
		dp := make([][]int, xLen+1)
		for i := 0; i <= xLen; i++ {
			dp[i] = make([]int, yLen+1)
		}
		for x := 0; x <= xLen; x++ {
			for y := 0; y <= yLen; y++ {
				if x == 0 || y == 0 {
					dp[x][y] = 0
				} else if X[x-1] == Y[y-1] {
					dp[x][y] = dp[x-1][y-1] + 1
				} else {
					dp[x][y] = max(dp[x-1][y], dp[x][y-1])
				}
			}
		}
		fmt.Fprintln(wtr, dp[xLen][yLen])
	}

	wtr.Flush()
}

Python: #coding:utf-8
from copy import deepcopy
n = int(input())

def lcs(X,Y):
    m = len(X)
    n = len(Y)
    c = [[False for i in range(n+1)] for j in range(m+1)]
    for i in range(m+1):
        c[i][0] = 0
    for i in range(n+1):
        c[0][i] = 0
    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
            elif c[i-1][j] >= c[i][j-1]:
                c[i][j] = c[i-1][j]
            else:
                c[i][j] = c[i][j-1]
    return c[m][n]
                            
        
for  i in range(n):
    A = input()
    B = input()
    a = lcs(A,B)
    print(a)

Python: q = int(input())
for i in range(q):
    X = input()
    Y = input()
    memo = [[0 for j in range(len(Y)+1)] for i in range(len(X)+1)]
    for i in range(1, len(X)+1):
        for j in range(1, len(Y)+1):
            x = X[:i]
            y = Y[:j]
            if x[-1] == y[-1]:
                memo[i][j] = memo[i-1][j-1] + 1
            else:
                memo[i][j] = max(memo[i-1][j], memo[i][j-1])
    print(memo[len(X)][len(Y)])

Python: def m():
 e=input
 a=''
 for _ in[0]*int(e()):
  X,z=e(),[]
  for y in e():
   s=i=0
   for k in z:
    t=X.find(y,s)+1
    if t<1:break
    if t<k:z[i]=t
    s=k;i+=1
   else:
    t=X.find(y,s)+1
    if t:z+=[t]
  a+=f'\n{len(z)}'
 print(a[1:])
if'__main__'==__name__:m()

Python: q = int(input())

for i in range(q):
    X = input()
    Y = input()
    x = len(X)
    y = len(Y)
    X = ' ' + X
    Y = ' ' + Y
    dp = [[0] *(y+1) for i in range(x+1)]
    for j in range(1, x + 1):
        for k in range(1, y + 1):
            if X[j] == Y[k]:
                dp[j][k] = dp[j - 1][k - 1] + 1
            else:
                dp[j][k] = max(dp[j - 1][k],dp[j][k - 1])
    print(dp[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 = 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: def lcs(str1, str2):
    lcslist = []
    for s in str2:
        m = n = 0
        for index in lcslist:
            t = str1.find(s, m) + 1
            if t <= 0:
                break
            elif t < index:
                lcslist[n] = t
            m = index
            n += 1
        else:
            t = str1.find(s, m) + 1
            if t > 0:
                lcslist.append(t)
    return len(lcslist)

if __name__ == '__main__':
    n = int(input())
    for i in range(n):
        str1 = input()
        str2 = input()
        print(lcs(str1, str2))

Python: q = int(input())

for k in range(q):
    x = list(input())
    y = list(input())
    lcs = [[0 for i in range(len(x)+1)] for j in range(len(y)+1)]
    for i in range(1,len(y) + 1):
        for j in range(1,len(x) + 1):
            if x[j-1] != y[i-1]:
                lcs[i][j] = max(lcs[i][j-1],lcs[i-1][j])
            else:
                lcs[i][j] = lcs[i-1][j-1] + 1
    print(lcs[len(y)][len(x)])

Python: def edit_distance(s, t):
 s = raw_input()
 t = raw_input()
 dp = {}
 for i in range(len(s) + 1):
  dp[i] = {0: i}
 for j in range(len(t) + 1):
  dp[0][j] = j
 for i in range(1, len(s) + 1):
  for j in range(1, len(t) + 1):
   if (s[i-1] == t[j-1]): 
    d = 0
   else:
    dp[i][j] = min(dp[i-1][j] + 1, dp[i][j-1] + 1, dp[i-1][j-1] + d)
 return dp[len(s)][len(t)]

Python: def calc(x,y):
    n = len(x)
    m = len(y)
    dp1 = [0]*(m+1)
    for i in range(n):
        dp2 = dp1[:]
        for j in range(m):
            if x[i] == y[j]:
                dp1[j+1] = dp2[j]+1
            elif dp1[j+1] < dp1[j]:
                dp1[j+1] = dp1[j]
    return dp1[-1]

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

Python: import sys


n = int(input())

primary = [0] * 1000
secondary = [0] * 1000


for i in range(n):
    s1 = sys.stdin.readline().strip()
    s2 = sys.stdin.readline().strip()

    len1 = len(s1)
    len2 = len(s2)

    for i in range(len1):
        primary[i] = 0
        secondary[i] = 0

    for i in range(len2):
        for j in range(len1):
            if s1[j] == s2[i]:
                matched = 1
            else:
                matched = 0

            if j == 0:
                secondary[j] = matched
            else:
                sc0 = secondary[j-1]
                pr0 = primary[j-1] + matched
                pr1 = primary[j]
                if sc0 > pr0:
                    if pr0 > pr1:
                        secondary[j] = sc0
                    elif sc0 > pr1:
                        secondary[j] = sc0
                    else:
                        secondary[j] = pr1
                else:
                    if sc0 > pr1:
                        secondary[j] = pr0
                    elif pr0 > pr1:
                        secondary[j] = pr0
                    else:
                        secondary[j] = pr1

        primary, secondary = secondary, primary

    print(primary[len1-1])

Python: m = int(input())
for i in range(m):
    str1 = input()
    str2 = input()
    A = [0 for j in range(len(str2)+1)]
    for char1 in str1:
        A_copy = A[:]
        for char2 in str2:
            if(char1==char2):
                A[k+1] = A_copy[k]+1
            elif(A[k] > A[k+1]):
                A[k+1] = A[k]
    print(A[-1])