Template: 11. DYNAMIC PROGRAMMING — 2D Template (Two Strings)

11. DYNAMIC PROGRAMMING — 2D Template (Two Strings)

# =============================================================================
def dp_2d_strings(s1, s2):
    m, n = len(s1), len(s2)
    dp = [[0] * (n + 1) for _ in range(m + 1)]

    # Base cases: dp[0][j] = ?, dp[i][0] = ?

    for i in range(1, m + 1):
        for j in range(1, n + 1):
            if s1[i - 1] == s2[j - 1]:
                dp[i][j] = dp[i - 1][j - 1] + 1  # match
            else:
                dp[i][j] = max(dp[i - 1][j], dp[i][j - 1])  # no match

    return dp[m][n]


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