https://www.acmicpc.net/problem/9251
시간 제한 : 0.1초
메모리 제한 : 256MB
x = input()
y = input()
dp = [[0] * (len(y) + 1) for _ in range(len(x) + 1)]
for i in range(1, len(x) + 1):
for j in range(1, len(y) + 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[len(x)][len(y)])