Go: package main

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

const (
	initialBufSize = 100000
	maxBufSize     = 1000000
)

var sc *bufio.Scanner

func initScanner(r io.Reader) *bufio.Scanner {
	buf := make([]byte, initialBufSize)

	sc := bufio.NewScanner(r)
	sc.Buffer(buf, maxBufSize)
	sc.Split(bufio.ScanWords) // bufio.ScanLines
	return sc
}

func main() {
	sc = initScanner(os.Stdin)
	resolve()
}

func resolve() {
	n := scanInt(sc)
	results := []int{}
	for i := 0; i < n; i++ {
		results = append(results, resolveInstance())
	}
	for _, v := range results {
		fmt.Println(v)
	}
	return
}

func resolveInstance() int {
	x, y := scanString(sc), scanString(sc)
	lx, ly := len(x), len(y)
	dp := make([][]int, lx+1)
	dp[0] = make([]int, ly+1)
	for i := 1; i <= lx; i++ {
		dp[i] = make([]int, ly+1)
		dp[i][0] = dp[i-1][0]
		for j := 1; j <= ly; j++ {
			dp[i][j] = dp[i-1][j]
			if dp[i][j] < dp[i][j-1] {
				dp[i][j] = dp[i][j-1]
			}
			if x[i-1] == y[j-1] {
				cL := dp[i-1][j-1] + 1
				if dp[i][j] < cL {
					dp[i][j] = cL
				}
			}
		}
	}
	return dp[lx][ly]
}

const (
	remove = 0 + iota
	match
)

// snip-scan-funcs
func scanInt(sc *bufio.Scanner) int {
	sc.Scan()
	i, _ := strconv.Atoi(sc.Text())
	return int(i)
}
func scanString(sc *bufio.Scanner) string {
	sc.Scan()
	return sc.Text()
}

Python: import sys

input = sys.stdin.readline


def solve(X, Y):
    m, n = len(X), len(Y)
    dp = [[0] * (n + 1) for _ in range(m + 1)]
    for i, x in enumerate(X, start=1):
        dp_i = dp[i]
        dp_im = dp[i - 1]
        for j, y in enumerate(Y, start=1):
            if x == y:
                dp_i[j] = dp_im[j - 1] + 1
            elif dp_im[j] > dp_i[j - 1]:
                dp_i[j] = dp_im[j]
            else:
                dp_i[j] = dp_i[j - 1]
    return dp[m][n]


def main():
    q = int(input())
    X = [None] * q
    Y = [None] * q
    for i in range(q):
        X[i] = input().rstrip()
        Y[i] = input().rstrip()

    ans = [solve(x, y) for x, y in zip(X, Y)]
    print("\n".join(map(str, ans)))


if __name__ == "__main__":
    main()

Python: def lcs(x, y):
    a = len(x)
    b = len(y)
    c1 = [0] * (b + 1)
    for i in range(a):
        e1 = x[i]
        c2 = c1[:]
        for j in range(b):
            if e1 == y[j]:
                c1[j+1] = c2[j] + 1
            elif c1[j+1] < c1[j]:
                c1[j+1] = c1[j]
    return c1[-1]
    
n = int(input().rstrip())
ret = []
for i in range(n):
    s1 = input().rstrip()
    s2 = input().rstrip()
    ret.append(lcs(s1, s2))
print(*ret, sep="\n")

Python: # -*- coding: utf-8 -*-
 
 
def main(x, y):
    answer = 0
    x_len = len(x) + 1
    y_len = len(y) + 1
    array = [[0] * y_len] * x_len
    # x[0] == y[0] ?????´??????????????????????????¨??????????????????
    x = ' ' + x
    y = ' ' + y
    for i in range(1, x_len):
        for j in range(1, y_len):
            if x[i] == y[j]:
                array[i][j] = array[i - 1][j - 1] + 1
            else:
                array[i][j] = max(array[i][j - 1], array[i - 1][j])
            answer = max(answer, array[i][j])
    return answer

if __name__ == '__main__': 
    n = int(input())
    for _ in range(n):
        x = input()
        y = input()
        print(main(x, y))

Python: for _ in range(int(input())):
    X = input()
    Y = input()
    dp = [[0 for y in range(len(Y)+1)] for x in range(len(X)+1)]
    for x in range(len(X) + 1):
        for y in range(len(Y) + 1):
            if x == 0 or y == 0:
                dp[x][y] = 0
            elif X[x-1] == Y[y-1]:
                dp[x][y] = dp[x-1][y-1] + 1
            else:
                dp[x][y] = max(dp[x-1][y], dp[x][y-1])
    print(dp[-1][-1])

Python: def lcs(X, Y):
    m = len(X)
    n = len(Y)
    c = [[0] * (n+1)] * (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
            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 = input()
    Y = 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)

def solve():
    N = int(input())
    for _ in range(N):
        x = input()
        y = input()
        print(lcs(x, y))

if __name__ == '__main__':
    solve()

Python: def findlcs(x, y):
    dp = [0]*(len(y)+1)

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

    return dp[len(y)]


q = int(input())
for k in range(q):
    X = input()
    Y = input()
    print(findlcs(X, Y))

Python: #!/usr/bin/env python
from __future__ import division, print_function
from sys import stdin


def main():
    num = int(stdin.readline())

    c = [range(1001) for _ in xrange(1001)]

    for _ in xrange(num):
        x = stdin.readline().rstrip()
        y = stdin.readline().rstrip()

        m = len(x)
        n = len(y)

        for i in xrange(m+1):
            row = c[i]
            for j in xrange(n+1):
                row[j] = 0

        cim1 = c[0]
        for i, xi in enumerate(x, start=1):
            ci = c[i]
            for j, yj in enumerate(y, start=1):
                if xi == yj:
                    ci[j] = cim1[j-1] + 1
                elif cim1[j] >= ci[j-1]:
                    ci[j] = cim1[j]
                else:
                    ci[j] = ci[j-1]
            cim1 = ci

        print(ci[j])


main()

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

	for i in range(1,xlen+1) :
		for j in range(1,ylen+1) :
			if X[i-1] == Y[j-1] : Z[i][j] = Z[i-1][j-1] + 1
			elif Z[i-1][j] >= Z[i][j-1] : Z[i][j] = Z[i-1][j]
			else : Z[i][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())

Python: import sys
sys.setrecursionlimit(100000)
q = int(input())

l = []
x = ""
y = ""
def lcs(yIndex, xIndex):
    global l, x, y
    if xIndex < 0 or yIndex < 0:
        return 0
    elif x[xIndex] == y[yIndex]:
        return 1 + lcs(yIndex - 1, xIndex - 1)
    else:
        return max(lcs(yIndex, xIndex - 1), lcs(yIndex - 1, xIndex))

for i in range(q):
    x = input()
    y = input()

    print(lcs(len(y) - 1, len(x) - 1))

Python: """
problem statment url: http://judge.u-aizu.ac.jp/onlinejudge/description.jsp?id=ALDS1_10_C
"""


def lcs():
	s1 = raw_input()
	s2 = raw_input()
	la, lb = len(s1), len(s2)
	dp1 = [0 for _ in range(lb + 1)]

	for i in range(la):
		dp2 = dp1 + []
		for j in range(lb):
			if s1[i] == s2[j]:
				dp1[j + 1] = dp2[j] + 1
			else:
				dp1[j + 1] = dp1[j] if dp1[j] > dp2[j + 1] else dp2[j + 1]

	return dp1[-1]

tc = int(raw_input())
for _ in range(tc):
	print(lcs())

Python: q = int(input())
for i in range(q):
    x = input()
    y = input()
    n = len(x)
    m = len(y)
    d = [0]*((n+1)*(m+1))
    for i in range(n):
        for j in range(m):
            if x[i] == y[j]:
                d[(n+1)*(j+1)+i+1] = d[(n+1)*j+i]+1
            else:
                d[(n+1)*(j+1)+i+1] = max(d[(n+1)*j+i+1],d[(n+1)*(j+1)+i])
    print(d[-1])