Go: package main

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

const (
	initialBufSize = 100000
	maxBufSize     = 1000000
)

var sc *bufio.Scanner

func initScanner(r io.Reader) *bufio.Scanner {
	buf := make([]byte, initialBufSize)

	sc := bufio.NewScanner(r)
	sc.Buffer(buf, maxBufSize)
	sc.Split(bufio.ScanWords) // bufio.ScanLines
	return sc
}

func main() {
	sc = initScanner(os.Stdin)
	resolve()
}

func resolve() {
	n := scanInt(sc)
	results := []int{}
	for i := 0; i < n; i++ {
		results = append(results, resolveInstance())
	}
	for _, v := range results {
		fmt.Println(v)
	}
	return
}

func resolveInstance() int {
	x, y := scanString(sc), scanString(sc)
	lx, ly := len(x), len(y)
	dp := make([][]int, lx+1)
	dp[0] = make([]int, ly+1)
	for i := 1; i <= lx; i++ {
		dp[i] = make([]int, ly+1)
		dp[i][0] = dp[i-1][0]
		for j := 1; j <= ly; j++ {
			dp[i][j] = dp[i-1][j]
			if dp[i][j] < dp[i][j-1] {
				dp[i][j] = dp[i][j-1]
			}
			if x[i-1] == y[j-1] {
				cL := dp[i-1][j-1] + 1
				if dp[i][j] < cL {
					dp[i][j] = cL
				}
			}
		}
	}
	return dp[lx][ly]
}

const (
	remove = 0 + iota
	match
)

// snip-scan-funcs
func scanInt(sc *bufio.Scanner) int {
	sc.Scan()
	i, _ := strconv.Atoi(sc.Text())
	return int(i)
}
func scanString(sc *bufio.Scanner) string {
	sc.Scan()
	return sc.Text()
}

Python: def lcs(x, y):
    m = len(x)
    n = len(y)
    c = [[0] * 1001 for i in range(1002)]
    x = " " + x
    y = " " + y
    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
            else:
                c[i][j] = max(c[i - 1][j], c[i][j - 1])
    return max([e for l1 in c for e in l1])

if __name__ == '__main__':
    n = int(input().rstrip())
    for i in range(n):
        s1 = input().rstrip()
        s2 = input().rstrip()
        print(lcs(s1, s2))

Python: import sys
sys.setrecursionlimit(10000)

def calc(x,y):
    i = len(x)
    j = len(y)
    if d[i][j]:
        return d[i][j]
    else:
        if i == 1:
            if x in y:
                d[i][j] = 1
                return 1
            else:
                d[i][j] = 0
                return 0
        elif j == 1:
            if y in x:
                d[i][j] = 1
                return 1
            else:
                d[i][j] = 0
                return 0
        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 = [[None for _ in range(len(y)+1)] for _ in range(len(x)+1)]
    print(calc(x,y))

Python:  
def lcs(X, Y):
    dp = [0]*(len(Y)+1)
     
    for x in X:
        tmp = dp[:]
        for j, y in enumerate(Y):
            if x == y:
                dp[j+1] = tmp[j] + 1
            elif dp[j+1] < dp[j]:
                dp[j+1] = dp[j]
                                
    return dp[-1]
 
n = int(input()) 

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

Python: def ask(X,Y):

 a=len(X)
 b=len(Y)
 Z=[]
 for n in range(a):
  z=0
  c=0
  for i in range(n,a):
   for j in range(c,b):
    if(c==b-1):
     break
    if(X[i]==Y[j]):
     z+=1
     c=j
     break
     
  Z.append(z)

 Z.sort();
 return Z[a-1]


q=int(input())
Z=[]
for p in range(q):
 x=input()
 X=list(x)
 y=input()
 Y=list(y)
 z=ask(X,Y)
 Z.append(z)

for p in range(q):
 print(Z[p])

Python: def answer(X, Y):
    m = len(X)
    n = len(Y)
    C = [[0 for _ in range(n + 1)] for _ in range(m + 1)]

    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][j - 1], C[i - 1][j])
    return C[m][n]


if __name__ == '__main__':
    q = int(input())
    for _ in range(q):
        X = input()
        Y = input()
        print(answer(X, Y))

Python: def Ics(X, Y):
    m = len(X)
    n = len(Y)
    c1 = [0] * (n + 1)
    for i in range(m):
        d = X[i]
        c2 = c1[:]
        for j in range(n):
            if (d == Y[j]):
                c1[j + 1] = c2[j] + 1
            elif (c1[j + 1] < c1[j]):
                c1[j + 1] = c1[j]
    return (c1[-1])

q = int(input().rstrip())
t = []
for i in range(q):
    s1 = input().rstrip()
    s2 = input().rstrip()
    t.append(Ics(s1, s2))
print(*t, sep = "\n")

Python: n = int(input())
p = []
a,b = [int(x) for x in input().split()]
p.append(a)
p.append(b)
for i in range(1, n):
    c,d = [int(x) for x in input().split()]
    p.append(d)
# end input
# create dp table
dp = []
for x in range(n+1):
    dp.append([0] * (n+1))

for l in range(2, n+1):
    for i in range(1, n-l+2):
        j = i + l -1
        dp[i][j] = 9999999999

        for k in range(i, j):
            tmp = dp[i][k] + dp[k+1][j] + (p[i-1] * p[k] * p[j])
            if dp[i][j] > tmp:
                dp[i][j] = tmp
#print(dp)
print(dp[1][n])

Python: # -*- coding: utf-8 -*-

import sys
sys.setrecursionlimit(10 ** 9)
def input(): return sys.stdin.readline().strip()
def INT(): return int(input())
def MAP(): return map(int, input().split())
def LIST(): return list(map(int, input().split()))

def LCS(A, B):
    N = len(A)
    M = len(B)
    dp = [[0] * (M+1) for i in range(N+1)]
    for i in range(N+1):
        for j in range(M+1):
            # 下に送る
            if i < N:
                dp[i+1][j] = max(dp[i+1][j], dp[i][j])
            # 右に送る
            if j < M:
                dp[i][j+1] = max(dp[i][j+1], dp[i][j])
            # 今回増やす文字が一致するなら、LCSが1文字増える
            if i < N and j < M and A[i] == B[j]:
                # 右下に送る
                dp[i+1][j+1] = max(dp[i+1][j+1], dp[i][j]+1)
    return dp[N][M]

Q=INT()

for _ in range(Q):
    a=input()
    b=input()
    print(LCS(a, b))

Python: def calc_lcs(X, Y):
    from array import array
    m = len(X)
    n = len(Y)
    X = ' ' + X
    Y = ' ' + Y
    c = array('I', [0] * (1001 * 1001))
    for i in range(1, m+1):
        for j in range(1, n+1):
            if X[i] == Y[j]:
                c[i*1001 + j] = c[(i-1)*1001 + j - 1] + 1
            elif c[(i-1)*1001 + j] >= c[i*1001 + j - 1]:
                c[i*1001 + j] = c[(i-1)*1001 + j]
            else:
                c[i*1001 + j] = c[i*1001 + j - 1]
    return max(c)


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_lcs(X, Y)

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

Python: 
def f(x,y):
	list=[0]
	for z in y:
		for i in range(len(list)-1,-1,-1):
			tmp=x.find(z,list[i])+1
			if tmp:
				if i+1 < len(list):
					list[i+1]=min(list[i+1],tmp)
				else:
					list.append(tmp)
	return len(list)-1
 
n=int(input())
for i in range(q):
	x=input()
	y=input()
	print(f(x,y))