Go: package main

import (
	. "fmt"
    "math"
)

// func init() { Println("----------------------------------------") }

func main() {
    const L_MAX = 1003

	var q int
	Scanf("%d", &q)
	X := make([]string, 0, 150)
	Y := make([]string, 0, 150)
	for i := 0; i < 2 * q; i++ {
	    var tmp string
	    Scanf("%s", &tmp)

	    if i % 2 == 0 {
	        X = append(X, tmp)
	    } else {
	        Y = append(Y, tmp)
	    }
	}

    for i := 0; i < q; i++ {
        dp := make([][]int, L_MAX)
        for k, _ := range dp {
            dp[k] = make([]int, L_MAX)
        }

        x, y := X[i], Y[i]

        // init
        isXFound := false
        for c := 0; c < len(x); c++ {
            if isXFound || y[0] == x[c] {
                dp[0][c] = 1
                isXFound = true
            }
        }
        isYFound := false
        for r := 0; r < len(y); r++ {
            if isYFound || x[0] == y[r] {
                dp[r][0] = 1
                isYFound = true
            }
        }

        for r := 1; r < len(y); r++ {
            for c := 1; c < len(x); c++ {
                // dp[r][c]
                if x[c] == y[r] {
                    dp[r][c] = int(math.Max(float64(dp[r - 1][c - 1] + 1), float64(dp[r][c])))
                }

                dp[r][c] = int(math.Max(float64(dp[r][c]), math.Max(float64(dp[r - 1][c]), float64(dp[r][c - 1]))))
            }
        }
        Println(dp[len(y) - 1][len(x) - 1])

        // LCSも求めておく
        // ans := ""
        // r, c := len(y) - 1, len(x) - 1
        // for r >= 0 && c >= 0 {
        //     if y[r] == x[c] {
        //         ans = string(x[c]) + ans
        //         r--
        //         c--
        //     } else {
        //         if dp[r - 1][c] > dp[r][c - 1] {
        //             r--
        //         } else {
        //             c--
        //         }
        //     }
        // }
        // Println(ans)
    }
}

Python: def prep_array(X, Y):
    c = [[0]*1001 for _ in range(1000+1)]
    return c


def calc_lcs(X, Y, c):
    m = len(X)
    n = len(Y)
    X = ' ' + X
    Y = ' ' + Y

    pre_row = c[0]
    for i in range(1, m+1):
        row = c[i]
        XX = X[i]
        for j in range(1, n+1):
            if XX == Y[j]:
                row[j] = pre_row[j - 1] + 1
            elif pre_row[j] >= row[j - 1]:
                row[j] = pre_row[j]
            else:
                row[j] = row[j - 1]
        pre_row = row
    return check_max(c)


def check_max(array):
    max_lcs = 0
    for row in array:
        temp_max = max(row)
        if temp_max > max_lcs:
            max_lcs = temp_max
    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_lcs(X, Y, prep_array(X, Y))

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

Python: def longest_common_seq(x, y):
    m, n = len(x), len(y)
    
    dp = []
    for _ in range(m+1):
        dp.append([0]*(n+1))

    for i in range(m):
        for j in range(n):
            if x[i] == y[j]:
                dp[i][j] = dp[i-1][j-1] + 1
            else:
                dp[i][j] = max(dp[i-1][j], dp[i][j-1])

    return dp[m-1][n-1]



if __name__ == '__main__':
    q = int(input())  # 1 .. 150
    for _ in range(q):
        x = input()
        y = input()
        l = longest_common_seq(x,y)
        print(l)

Python: import numpy as np
q = int(input())

for _ in range(q):
    X = np.array([ord(i) for i in input()])
    Y = np.array([ord(i) for i in input()])
    NX = len(X)
    NY = len(Y)
    dp = np.zeros((NX+1,NY+1), dtype=np.int64)
    for x in range(NX):
        yes = Y == X[x]
        no = Y != X[x]
        dp[x+1][1:][yes] = dp[x][:-1][yes] + 1
        dp[x+1][1:][no] = np.maximum(dp[x][1:][no], dp[x][:-1][no])
    print(dp[NX][NY])

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]):
     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: #coding:UTF-8
def LCS(X,Y):
    count=0
    xlist=list(X)
    ylist=list(Y)
    anslist=[]
    ynum=0
    xnum=0
    yflag=False
    for i in range(len(ylist)):
        for j in range(i,len(xlist)):
            anslist.append([j,i])
    for i in range(len(anslist)):
        if xlist[anslist[i][0]]==ylist[anslist[i][1]] and ynum==anslist[i][1] and anslist[i][0]>=xnum:
            count+=1
            yflag=True
            ynum+=1
            xnum=anslist[i][0]
        if anslist[i][0]==len(xlist)-1:
            if yflag==True:
                yflag=False
            else:
                ynum+=1
    print(count)
if __name__=="__main__": 
    n=int(input())
    for i in range(n):
        X=input()
        Y=input()
        LCS(X,Y)

Python: def lcs(x,y,l,j,k):
	if(j==0 or k==0):
		return
	if(x[j-1]==y[k-1]):
		lcs(x,y,l,j-1,k-1)
		global c
		c+=1
	else:
		if l[j-1][k]>=l[j][k-1]:
			lcs(x,y,l,j-1,k)
		else:
			lcs(x,y,l,j,k-1)

q=int(input())
c=0
for i in range(q):
	x=list(input())
	y=list(input())
	l=[[0 for i in range(len(y)+1)] for j in range(len(x)+1)]

for j in range(1, len(x) + 1):
    for k in range(1, len(y) + 1):
        if x[j - 1] == y[k - 1]:
            a = 1
        else:
            a = 0
        l[j][k] = max(l[j-1][k-1] + a, l[j-1][k], l[j][k-1])
lcs(x,y,l,len(x),len(y))
print(c)

Python: #!/usr/bin/env python
# -*- coding: utf-8 -*-
"""
input:
3
abcbdab
bdcaba
abc
abc
abc
bc

output:
4
3
2

"""
import sys

sys.setrecursionlimit(int(1e5))


def lcs(A, B):
    m, n = len(A), len(B)
    dp = tuple([[0] * (n + 1) for _ in range(m + 1)])
    max_l = 0
    for i in range(1, m + 1):
        for j in range(1, n + 1):
            if A[i - 1] == B[j - 1]:
                dp[i][j] = dp[i - 1][j - 1] + 1
            else:
                dp[i][j] = max(dp[i - 1][j], dp[i][j - 1])
            max_l = max(max_l, dp[i][j])

    return max_l


def lcs_recursive(A, B, m, n):
    if m == 0 or n == 0:
        return 0
    elif A[m - 1] == B[n - 1]:
        return 1 + lcs_recursive(A, B, m - 1, n - 1)
    else:
        return max(lcs_recursive(A, B, m, n - 1), lcs_recursive(A, B, m - 1, n))


if __name__ == '__main__':
    _input = sys.stdin.readlines()
    pair_num = int(_input[0])

    word_list = _input[1:]
    # assert len(word_list) == 2 * pair_num
    # for k in range(0, len(word_list), 2):
    #     print(lcs(word_list[k].strip(), word_list[k + 1].strip()))

    for pair in zip(word_list[::2], word_list[1::2]):
        w1, w2 = map(lambda x: x.strip(), pair)
        # l1, l2 = len(w1), len(w2)
        print(lcs(w1, w2))

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