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: # -*- coding: utf-8 -*-
from itertools import product

N = int(input())

def calc_LCS(n, m):
    if n == 0 or m == 0:
        return 0
    elif X[n] == Y[m]:
        LCS[n][m] = LCS[n-1][m-1] + 1
        return LCS[n][m]
    else:
        LCS[n][m] = max(LCS[n-1][m], LCS[n][m-1])
        return LCS[n][m]
        

for _ in range(N):
    X = input()
    Y = input()
    LCS = [[0 for _ in range(len(Y) + 1)] for _ in range(len(X) + 1)]
    max_ = 0
    for n, m in product(range(1, len(X)+1), range(1, len(Y)+1)):        
        if X[n-1] == Y[m-1]:
            LCS[n][m] = LCS[n-1][m-1] + 1  
        else:
            LCS[n][m] = max(LCS[n-1][m], LCS[n][m-1])

    print(LCS[-1][-1])

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
   z[i]=min(t,k)
   s=k;i+=1
  else:
   t=X.find(y,s)+1
   if t:z+=[t]
 print(len(z))

Python: n = int(input())
dataset = []
for i in range(n):
    tmp = []
    tmp.append(input())
    tmp.append(input())
    dataset.append(tmp)

for data in dataset:
    m = len(data[0])
    n = len(data[1])
    i, j = 0, 0
    dp = []
    for x in range(n+1):
        dp.append([0] *(m+1))

    lcs = 0
    for j in range(n):
        for i in range(m):
            if data[0][i] == data[1][j]:
                dp[j+1][i+1] = dp[j][i] + 1
            else:
                dp[j+1][i+1] = max(dp[j+1][i], dp[j][i+1])

            if dp[j+1][i+1] > lcs:
                lcs = dp[j+1][i+1]
        
    print(lcs)

Python: from collections import defaultdict


def longest_common_subsequence(s, t):
    dp = [[0] * (len(t) + 1) for _ in range(len(s) + 1)]
    for i in range(len(s)):
        for j in range(len(t)):
            if s[i] == t[j]:
                dp[i + 1][j + 1] = dp[i][j] + 1
            else:
                dp[i + 1][j + 1] = max(dp[i + 1][j], dp[i][j + 1])
    return dp[-1][-1]


def longest_common_subsequence2(s, t):
    dp = [0] * (len(t) + 1)
    for i in range(len(s)):
        si = s[i]
        tmp = dp[:]
        for j in range(len(t)):
            if si == t[j]:
                dp[j + 1] = tmp[j] + 1
            else:
                dp[j + 1] = max(dp[j + 1], dp[j])
    return dp[-1]


def main():
    n = int(input())
    for _ in range(n):
        X, Y = input(), input()
        print(longest_common_subsequence2(X, Y))


if __name__ == '__main__':
    main()

Python: import sys
N = int(input())

for _ in range(N):
    x = sys.stdin.readline()
    y = sys.stdin.readline()
    m, n = len(x), len(y)
    dp = [[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]:
                dp[i][j] = dp[i-1][j-1] + 1
            else:
                dp[i][j] = max(dp[i][j-1], dp[i-1][j])
                
    print(dp[m][n])

Python: def main():
    n = int(input())
    result = []
    for i in range(n):
        a = input()
        b = input()
        array = [[1 for i in range(len(a))] for j in range(len(b))]
        for i in range(1, len(a)):
            for j in range(1, len(b)):
                c = 0
                if a[j] == b[i]:
                    c = 1
                array[i][j] = max(
                                    array[i-1][j],
                                    array[i][j-1],
                                    array[i-1][j-1]+c)
        result.append(array[len(a)-1][len(b)-1])
    for i in result:
        print(i)
if __name__ == "__main__":
    main()

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


def search(x, y):
    x_length = len(x)
    y_length = len(y)
    memo = [[0] * y_length for i in range(x_length)]
    for i in range(x_length):
        for j in range(y_length):
            if i == 0 or j == 0:
                if x[i] == y[j]:
                    memo[i][j] = 1
                else:
                    memo[i][j] = 0
            elif x[i] == y[j]:
                memo[i][j] = memo[i-1][j-1] + 1
            else:
                memo[i][j] = max(memo[i-1][j], memo[i][j-1])
    return memo[i][j]


if __name__ == "__main__":
    n = int(input())
    strs = [list(val) for val in sys.stdin.read().splitlines()]
    for i in range(n):
        print(search(strs[i*2], strs[i*2+1]))

Python: n = int(input())
for i in range(n):
    a = input()
    b = input()
    la = len(a) + 1
    lb = len(b) + 1
    L = [[0 for j  in range(la)] for k in range(lb)]
    for  m in range(1, la):
        for n in range(1, lb):
            if a[m-1] == b[n-1]:
                L[n][m] = L[n-1][m-1] + 1
            else:
                L[n][m] = max(L[n-1][m], L[n][m-1])
    print(L[-1][-1])

Python: def get_longest_count(X, Y):
  offsets = [0]
  for y in Y:
    tmp = offsets[:]
    for i, o in enumerate(offsets):
      j = X.find(y, o)
      if j < 0: break
      if i < len(offsets) - 1:
        tmp[i + 1] = min(offsets[i + 1], j + 1)
      else:
        tmp.append(j + 1)
    offsets = tmp
  return len(offsets) - 1

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

Python: 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+=[z]
print(*map(len,a),sep='\n')

Python: def Ics(x, y):
    a = len(x)
    b = len(y)
    c1 = [0] * (b + 1)

    for i in range(a):
        d = x[i]
        c2 = c1[:]
        for j in range(b):
            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())
r = []
for k in range(q):
    s1 = input().rstrip()
    s2 = input().rstrip()
    r.append(Ics(s1, s2))

print(*r, sep = "/n")

Python: def LCS(S, T):
    LS = len(S); LT = len(T)
    if LT > LS:
        S, T = T, S
        LS, LT = LT, LS
    dp = [0] * (LT + 1)
    for s in S:
        dp_pre=dp[:]
        for j, t in enumerate(T):
            if s == t:
                dp[j + 1] = dp_pre[j] + 1
            elif dp[j + 1] < dp[j]:
                dp[j + 1] = dp[j]
    return dp[-1]

for _ in range(int(input())):
    print(LCS(input(), input()))

Python: def L(str1,str2):
    A = [0 for _ in range(len(str2)+1)]
    for char1 in str1:
        A_copy = A[:]
        for j,char2 in enumerate(str2):
            if(char1==char2):
                A[j+1] = A_copy[j]+1
            elif(A[j] > A[j+1]):
                A[j+1] = A[j]
    return A[-1]


m = int(input())
for i in range(m):
    str1 = input()
    str2 = input()
    print(L(str1,str2))