Go: package main

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

func max(x, y int) int {
	if x < y {
		return y
	} else {
		return x
	}
}

func main() {
	scanner := bufio.NewScanner(os.Stdin)
	scanner.Scan()
	n, _ := strconv.Atoi(scanner.Text())
	for i := 0; i < n; i++ {
		scanner.Scan()
		s1 := scanner.Text()
		scanner.Scan()
		s2 := scanner.Text()
		s1, s2 = " " + s1 , " " + s2
		c := make([][]int, len(s1))
		for i := range c {
			c[i] = make([]int, len(s2))
		}

		LCS := 0

		for i := 1; i < len(s1); i++ {
			for j := 1; j < len(s2); j++ {
				if s1[i] == s2[j] {
					c[i][j] = c[i-1][j-1] + 1
				} else {
					c[i][j] = max(c[i-1][j], c[i][j-1])
				}
				LCS = max(LCS, c[i][j])
			}
		}
		fmt.Println(LCS)
	}
}

Python: def lcs_better(X, Y):
    costs = [0]
    for c in Y:
        for i in range(len(costs) - 1, -1, -1):
            tmp = X.find(c, costs[i])
            if tmp + 1:
                if i + 1 < len(costs):
                    costs[i + 1] = min(costs[i + 1], tmp + 1)
                else:
                    costs.append(tmp + 1)
    return len(costs) - 1


def answer(X, Y):
    m, n = len(X), len(Y)
    C = [[0] * (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 = list(input())
        Y = list(input())
        print(lcs_better(X, Y))

Python: def lcs_len(x, y):
    indices = [0]
    for y_i in y:
        t_index = c_index = 0
        for i in range(1, len(indices) + 1):
            c_index = x.find(y_i, t_index) + 1
            if c_index:
                if i < len(indices):
                    t_index = indices[i]
                    indices[i] = min(c_index, t_index)
                else:
                    indices.append(c_index)
                    break
    print(len(indices) - 1)
n = int(input())
for i in range(n):
    lcs_len(input(), input())

Python: def main():
    N = int(input())

    string_data = [input() for _ in range(N * 2)]

    for _ in range(N):
        s = string_data.pop(0)
        t = string_data.pop(0)

        dp = [0] * (len(t) + 1)

        for i, sc in enumerate(s):
            tmp = dp[:]
            for j, tc in enumerate(t):
                if sc == tc:
                    dp[j + 1] = tmp[j] + 1
                elif dp[j + 1] < dp[j]:
                    dp[j + 1] = dp[j]

        print(dp[-1])


if __name__ == '__main__':
    main()

Python: def lcs(x, y):
    lx = len(x)
    ly = len(y)
    pcsl = [[0 for i in range(ly + 1)] for j in range(lx + 1)]
    for i in range(lx):
        for j in range(ly):
            if x[i] == y[j]:
                pcsl[i][j] = pcsl[i - 1][j - 1] + 1
            else:
                pcsl[i][j] = max(pcsl[i - 1][j], pcsl[i][j - 1])
    print(pcsl[i][j])


q = int(input())

for i in range(q):
    ax = input()
    ay = input()
    lcs(ax, ay)

Python: n=int(input())

for i in range(n):
    a=list(input())
    b=list(input())

    r=[[0 for j in range(len(b)+1)]for i in range(len(a)+1)]

    for j in range(1,len(a)+1):
        for k in range(1,len(b)+1):
            c=max(r[j-1][k-1],r[j-1][k],r[j][k-1])
            
            if a[j-1]==b[k-1]:
                c=c+1
            
            r[j][k]=c
    print(r[len(a)][len(b)])

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 not t: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: #dj 16D8101012J ito jun
import sys
def search(a,b):
    na=len(a)
    nb=len(b)
    array = [[0]*(nb+1) for _ in range(na+1)]
    for i,x in enumerate(a,1):
        prerow=array[i-1]
        row=array[i]
        for j,y in enumerate(b,1):
            if x == y:
                row[j]=prerow[j-1]+1
            elif prerow[j] < row[j-1]:
                row[j] = row[j-1]
            else:
                row[j] = prerow[j]
    return array[-1][-1]

n = int(input())
strs = [list(i) for i in sys.stdin.read().splitlines()]
result = [search(strs[i*2], strs[i*2+1]) for i in range(n)]
print(*result, sep="\n")

Python: q = int(input().rstrip())
data_set = [[[i for i in input().rstrip()],
             [i for i in input().rstrip()]] for i in range(q)]

common_list = [[0] * 1000 for i in range(1000)]


def lcs(X: list, Y: list):
    global common_list
    m, n = len(X), len(Y)
    for i in range(1, m + 1):
        for k in range(1, n + 1):
            if X[i - 1] == Y[k - 1]:
                common_list[i][k] = common_list[i - 1][k - 1] + 1
            elif common_list[i - 1][k] >= common_list[i][k - 1]:
                common_list[i][k] = common_list[i - 1][k]
            else:
                common_list[i][k] = common_list[i][k - 1]
    return common_list[m][n]


for l, r in data_set:
    print(lcs(l, r))

Python: import sys
def lcs(X, Y):
    m = len(X)
    n = len(Y)
    # c = [[0 for i in range(n+1)] for i in range(m+1)]
    c = [None]*(m+1)
    for i in range(m+1):
        c[i] = [0]*(n+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
            elif c[i -1][j] >= c[i][j - 1]:
                c[i][j] = c[i-1][j]
            else:
                c[i][j] = c[i][j-1]
    return str(c[m][n])

q = int(input())
for i in range(q):
    X = sys.stdin.readline().rstrip('\r\n')
    Y = sys.stdin.readline().rstrip('\r\n')
    print(lcs(X, Y))

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

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

Python: 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 search(X, Y):
    dp = [[0] * (len(Y)+1) for x in range(len(X)+1)]
    for x in range(1, len(X) + 1):
        for y in range(1, len(Y) + 1):
            if X[x-1] == Y[y-1]:
                dp[x][y] = dp[x-1][y-1] + 1
            elif dp[x-1][y] > dp[x][y-1]:
                dp[x][y] = dp[x-1][y]
            else:
                dp[x][y] = dp[x][y-1]
    return dp[-1][-1]

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