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🔤 Subsequence Arena

Find Longest Common Subsequence • Trace the DP table!

📝 Input Strings

📊 LCS DP Table

📐 LCS Formula

if s1[i] == s2[j]:
  dp[i][j] = 1 + dp[i-1][j-1] ↖

else:
  dp[i][j] = max(dp[i-1][j], dp[i][j-1])
  ↑ or ←
String 1
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String 2
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LCS Length
?

🎯 Arrow Legend

↖ = Characters match!
↑ = Take from top
← = Take from left

💡 Key Insight

When characters match, we extend the LCS. Otherwise, we take the best from excluding either character.