Go: package main

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

type Position struct {
	X int
	Y int
}

func main() {
	sc := bufio.NewScanner(os.Stdin)
	sc.Split(bufio.ScanWords)
	n, err := nextInt(sc)
	if err != nil {
		panic(err)
	}
	for i := 0; i < n; i++ {
		strX := nextText(sc)
		strY := nextText(sc)
		fmt.Println(calcLcs(strX, strY))
	}
}

func calcLcs(strX, strY string) int {
	return lcs(strX, strY, Position{0, 0}, make(map[Position]int))
}

func lcs(strX string, strY string, position Position, memo map[Position]int) int {
	if position.X >= len(strX) || position.Y >= len(strY) {
		return 0
	}
	if v, ok := memo[position]; ok {
		return v
	}
	if strX[position.X] == strY[position.Y] {
		result := lcs(strX, strY, Position{position.X + 1, position.Y + 1}, memo)
		memo[position] = result + 1
		return memo[position]
	} else {
		result1 := lcs(strX, strY, Position{position.X + 1, position.Y}, memo)
		result2 := lcs(strX, strY, Position{position.X, position.Y + 1}, memo)
		var result int
		if result1 > result2 {
			result = result1
		} else {
			result = result2
		}
		memo[position] = result
		return result
	}
}

func nextInt(sc *bufio.Scanner) (int, error) {
	sc.Scan()
	return strconv.Atoi(sc.Text())
}

func nextText(sc *bufio.Scanner) string {
	sc.Scan()
	return sc.Text()
}

Python: from sys import stdin

X = [ 0 for i in range(1000) ]
Y = [ 0 for i in range(1000) ]
Z = [[0 for i in range(1000)]for i in range(1000)]

def getLCS(l) :
	xlen = len(X[l])
	ylen = len(Y[l])

	for i in range(1,xlen+1) :
		for j in range(1,ylen+1) :
			a = 1 if X[l][i-1] == Y[l][j-1] else 0
			Z[i][j] = max(Z[i-1][j-1] + a, Z[i-1][j], Z[i][j-1])

	return Z[xlen][ylen]

n = int(input())
for l in range(n) :
	X[l] = stdin.readline().strip()
	Y[l] = stdin.readline().strip()
	print(getLCS(l))

Python: for _ in[0]*int(input()):
 X,z=input(),[]
 for y in input():
  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]
 print(len(z))

Python: q = int(input())

l = []
x = ""
y = ""

for i in range(q):
    x = input()
    y = input()
 
    yLen = len(y)
    xLen = len(x)
    l = [[0] * (xLen + 1) for j in range(yLen + 1)]

    for j in range(1, yLen + 1):
        for k in range(1, xLen + 1):
            if x[k - 1] == y[j - 1]:
                l[j][k] = 1 + l[j - 1][k - 1]
            else:
                if l[j][k - 1] > l[j - 1][k]:
                    l[j][k] = l[j][k - 1]
                else:
                    l[j][k] = l[j - 1][k]
 
    print(l[yLen][xLen])

Python: q = int(input())

for __ in range (q):

    S1 = input()
    S2 = input()
    dp = [[0 for i in range(len(S2)+1+10)] for j in range(len(S1)+1+10)]


    for i in range (len(S1)):
        for j in range (len(S2)):
            if S1[i] == S2[j]:
                dp[i+1][j+1] = max(dp[i+1][j]+1,dp[i+1][j]+1)
            else:
                dp[i+1][j+1] = max(dp[i+1][j],dp[i][j+1])

    print(dp[len(S1)][len(S2)])

Python: import sys
input = lambda: sys.stdin.readline().rstrip()

def lcs(x, y):
    dp = [0  for _ in range(len(y)+1)]
    for i in range(len(x)):
        tmp = dp[:]
        num = x[i]
        for j in range(len(y)):
            if num == y[j]:
                dp[j+1] = tmp[j] + 1
            elif dp[j+1] < dp[j]:
                dp[j+1] = dp[j]  
    return dp[-1]

n=int(input())
for _ in range(n):
    print(lcs(input(),input()))

Python: def main():
    n = int(input())
    for i in range(n):
        a = input()
        b = input()
        na=len(a)
        nb=len(b)
        array = [[1]*nb]*na
        #array = [[0 for i in range(nb)] for j in range(na)]
        print(array)
        for i in range(na):
            for j in range(nb):
                if i==0:
                    if a[i]==b[j]:
                        array[i][j]=1
                elif j==0:
                    if a[i]==b[j]:
                        array[i][j]=1
                else:
                    c = 0
                    if a[i] == b[j]:
                        c = 1
                    array[i][j] = array[i-1][j-1]+c 
                    max(
                            array[i-1][j],
                            array[i][j-1],
                            array[i-1][j-1]+c)
        print(array[na-1][nb-1])
if __name__ == "__main__":
    main()

Python: import sys


def lcs(x, y):
    # Creating len(x + 1) * len(y + 1) table
    x = ' ' + x  # Add Space
    y = ' ' + y  # Add Space
    len_x = len(x)
    len_y = len(y)
    table = []
    for _ in range(len_y):
        table.append([0] * len_x)

    maxl = 0
    for i, x_ch in enumerate(x):
        if i == 0: continue
        for j, y_ch in enumerate(y):
            if j == 0: continue
            if x[i] == y[j]:
                table[j][i] = table[j - 1][i - 1] + 1
            else:
                table[j][i] = max(table[j - 1][i], table[j][i - 1])
            maxl = max(maxl, table[j][i])

    return maxl


if __name__ == "__main__":
    lines = [line.strip() for line in sys.stdin.readlines()[1:]]
    for sequence_pair in zip(lines[::2], lines[1::2]):
        print(lcs(*sequence_pair))

Python: def lcs(X, Y):
    m, n = len(X), len(Y)
    c = [[0 for i in range(n+1)] for j 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-1][j], c[i][j-1])
    return c[m][n]

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

Python: def lcs(l1,l2):
    dp=[[0 for x in range(len(l2)+1)] for y in range(len(l1)+1)]

    for i in range(1,len(l1)+1):
        for j in range(1,len(l2)+1):
            if l1[i-1]==l2[j-1]:
                dp[i][j]=dp[i-1][j-1]+1
            else:
                dp[i][j]=max(dp[i-1][j],dp[i][j-1])
                
    return dp[len(l1)][len(l2)]


a=[]
n=int(input())
for i in range(n):
    l1=list(input())
    l2=list(input())
    a+=[lcs(l1,l2)]

for i in range(n):
    print(a[i])

Python: def calc_lcs(X, Y):
    from array import array
    max_lcs = 0
    m = len(X)
    n = len(Y)
    X = ' ' + X
    Y = ' ' + Y
    c = array('b', [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]
            max_lcs = max(max_lcs, c[i*1001 + j])
    return max_lcs


if __name__ == '__main__':
    # ??????????????\???
    num = int(input())
    # num = 1

    for _ in range(num):
        X = input()
        Y = input()
        # X = 'abcbdab'
        # Y = 'bdcaba'


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

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

Python: n = int(input())
for _ in range(n):
    a, b = input(), input()
    i, j = len(a), len(b)
    prev = [0] * (j + 1)
    for ca in a:
        cur = [0] * (j + 1)
        for l, cb in enumerate(b):
            if ca == cb:
                cur[l + 1] = prev[l] + 1
            else:
                cur[l + 1] = max(cur[l], prev[l + 1])
        prev = cur
    print(prev[-1])

Python: import sys
sys.setrecursionlimit(10000)
def lcs(X, Y):
    i = len(X)
    j = len(Y)
    if not i or not j:
        return 0
    if memo[i][j] >= 0:
        return memo[i][j]
    if X[-1] == Y[-1]:
        memo[i][j] = 1 + lcs(X[:-1], Y[:-1])
        return memo[i][j]
    else:
        memo[i][j] = max(lcs(X[:-1], Y), lcs(X, Y[:-1]))
        return memo[i][j]

q = int(input())
for i in range(q):
    X = input()
    Y = input()
    memo = [[-1 for j in range(len(Y) + 1)] for i in range(len(X) + 1)]
    print(lcs(X, Y))