Go: package main

import "fmt"

func initialize_grid(width int,height int)[][]int{
	var grid [][]int
	for i:=0;i<height+1;i++{
		var grid_row  []int
		for j:=0;j<width+1;j++{
			grid_row = append(grid_row,0)
		}
		grid = append(grid,grid_row[:])
	}
	return grid
}

func ma(x int,y int)int{
	if x >= y{
		return x
	}else{
		return y
	}
}

func main()  {
	//Take input
	var num int
	var st1,st2 string
	var string_pairs [][]string
	fmt.Scan(&num)
	for i:=0;i<num;i++{
		var string_pair []string
		fmt.Scan(&st1)
		fmt.Scan(&st2)
		string_pair = append(string_pair,st1,st2)
		string_pairs = append(string_pairs,string_pair)
	}
	//DP
	//initialize grid
	for i:=0;i<num;i++{
		string_1 := string_pairs[i][0]
		string_2 := string_pairs[i][1]

		dp := initialize_grid(len(string_2),len(string_1))

		for j:=1;j<len(string_1)+1;j++{
			for k:=1;k<len(string_2)+1;k++{
				if string_1[j-1] == string_2[k-1]{
					dp[j][k] = dp[j-1][k-1] + 1
				}else{
					dp[j][k] = ma(dp[j-1][k],dp[j][k-1])
				}
			}
		}
		fmt.Println(dp[len(string_1)][len(string_2)])
	}
}

Python: q = int(input())
ans = []

for i in range(q):
    s1 = input()
    n1 = len(s1)
    s2 = input()
    n2 = len(s2)

    f = [[0 for j in range(n2)] for i in range(n1)]
    if s1[0] == s2[0]:
        f[0][0] = 1
    else:
        f[0][0] = 0

    for j in range(1, n2):
        if f[0][j-1] == 0:
            if s1[0] == s2[j]: delta = 1
            else: delta = 0
            f[0][j] = f[0][j-1]+delta
        else:
            f[0][j] = f[0][j-1]

    for i in range(1, n1):
        if f[i-1][0] == 0:
            if s1[i] == s2[0]: delta = 1
            else: delta = 0
            f[i][0] = f[i-1][0]+delta
        else:
            f[i][0] = f[i-1][0]

    for i in range(1, n1):
        for j in range(1, n2):
            if s1[i] == s2[j]:
                f[i][j] = f[i-1][j-1]+1
            else:
                f[i][j] = max(f[i-1][j], f[i][j-1])

    ans.append(f[n1-1][n2-1])
    #print(f)

for a in ans:
    print(a)

Python: q = int(input())
for _ in range(q):
    x = input()
    y = input()
    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):
        tmp = x[i - 1]
        for j in range(1, n + 1):
            if tmp == 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]
    print(c[m][n])

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: import sys

def dp_init(m, n):
    ret = []
    for i in range(m):
        ret.append([None] * n)
    return ret

def solve(str_a, str_b):
    dp = dp_init(len(str_a), len(str_b))
    return rec(len(str_a), len(str_b), str_a, str_b, dp, 0)

def rec(i, j, str_a, str_b, dp, depth):
    if dp[i-1][j-1] is not None:
        #print(dp)
        #print(" "*depth + "(%d, %d) : %d - hit" % (i-1, j-1, dp[i-1][j-1]))
        return dp[i-1][j-1]
    if i-1 == 0 or j-1 == 0:
        dp[i-1][j-1] = 0
        #print(" "*depth + "(%d, %d) : %d - zero" % (i-1, j-1, dp[i-1][j-1]))
        return 0
    if str_a[i-1] == str_b[j-1]:
        dp[i-1][j-1] = rec(i-1, j-1, str_a, str_b, dp, depth+1) + 1
        #print(" "*depth + "(%d, %d) : %d" % (i-1, j-1, dp[i-1][j-1]))
        return dp[i-1][j-1]

    dp[i-1][j-1] = max(rec(i, j-1, str_a, str_b, dp, depth+1), rec(i-1, j, str_a, str_b, dp, depth+1))
    #print(" "*depth + "(%d, %d) : %d" % (i-1, j-1, dp[i-1][j-1]))
    return dp[i-1][j-1]

nb_pairs = int(input())
pairs = []
for i in range(0, nb_pairs):
    pairs.append((input(), input()))

for i in range(0, nb_pairs):
    str_a, str_b = pairs[i]
    print(solve(str_a, str_b))

Python: from sys import stdin
input = stdin.readline

q = int(stdin.readline())

def solve():
    xs = input()
    ys = input()
    len_x = len(xs)-1
    len_y = len(ys)-1
    # [i,j]までで一番長い数値とする
    dp = [0] * (len_x+1)
    memo = [0] * (len_x+1)

    for j in range(len_y):
        yj = ys[j]
        # 参照コピーにならない
        memo = dp[:]
        for i in range(len_x):
            if xs[i] == yj:
                dp[i+1] = memo[i] + 1
            elif dp[i+1] < dp[i]:
                dp[i+1] = dp[i]
    return dp[len_x]


ret = [ solve() for i in range(q)]
print(*ret, sep="\n")

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: def lcs(X, Y):
    m, n = len(X), len(Y)
    memo = [[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]:
                memo[i][j] = memo[i - 1][j - 1] + 1
            else:
                memo[i][j] = max(memo[i][j - 1], memo[i - 1][j])
    return memo[m][n]

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

Python: def lcs(s1, s2):
    dp = []
    for s2_k in s2:
        bgn_idx = 0
        for i, cur_idx in enumerate(dp):
            chr_idx = s1.find(s2_k, bgn_idx) + 1
            if not chr_idx:
                break
            dp[i] = min(cur_idx, chr_idx)
            bgn_idx = cur_idx
        else:
            chr_idx = s1.find(s2_k, bgn_idx) + 1
            if chr_idx:
                dp.append(chr_idx)
    return len(dp)


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

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)]
        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: q = int(input())

for _ in range(q):
    X, Y = input(), input()
    n_X, n_Y = len(X), len(Y)

    dp = [[0 for _ in range(n_Y + 1)] for _ in range(n_X + 1)]
    for i in range(n_X):
        X_i = X[i]
        dp_i = dp[i]
        dp_i1 = dp[i + 1]
        for j in range(n_Y):
            if X_i == Y[j]:
                x = 1
            else:
                x = 0
            dp_i1[j + 1] = max(dp_i[j] + x, dp_i1[j], dp_i[j + 1])
    print(dp[n_X][n_Y])