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Advanced digit DP problem-solving techniques
What you'll practice
Quick refresher
Start leaning basics.
Adjacent digit constraint
Track the previous digit
The code
Start leaning basics.
Key takeaways
Count digit occurrences
Count contributions per position
The code
Complexity analysis
Key takeaways
Test your understanding
Limit non-zero digits
Count non-zeros placed
Pruning invalid paths
The code
Key takeaways
Permutations with divisibility
Too many permutations
Track used positions and remainder
The code
Key takeaways
Test your understanding
Position-dependent rules
Enforce different rules at even/odd positions
The code
Start leaning basics.
Complexity analysis
Key takeaways
Palindrome structure
Only half the digits are free
The code
Key takeaways
Test your understanding
Sum instead of count
Return a pair from DP
The code
Start leaning basics.
Complexity analysis
Key takeaways
Divisibility by own digits
Track remainder mod 2520
The code
Start leaning basics.
Complexity analysis
Key takeaways
Test your understanding
Binary digit DP
Work with bits, not decimal digits
The code
Start leaning basics.
Key takeaways
What to watch out for
Comprehensive check
Continue your practice
Summary