Opening scenario
Problem references use LC for LeetCode.
numsballoons sit in a row. Bursting ballooniearnsnums[i-1] * nums[i] * nums[i+1]coins, treating out-of-range as1. The burst balloon is removed and its neighbors become adjacent. Maximize total coins (LC 312, Burst Balloons). Then the interviewer moves to a string. Partition it into palindromes: return the fewest cuts that leave every piece a palindrome. Or run the strange printer: each pass prints one contiguous block of the same character on top of what is already there. Return the fewest passes that build the string.
Balloon values are non-negative, and each burst uses the balloon’s current surviving neighbors. For the printer, a pass may overwrite earlier characters; the final string must match the target exactly. Begin by asking which choice would leave fixed boundaries around smaller subproblems.
Question progression
Q1 — Why does "which balloon to burst first" lead nowhere, and what's the state?
Question: You try dp[i][j] = max coins from…
In the full tutorial
- Canonical Template
- Complexity
- Pattern Recognition Signals
- Practice Set
- Pitfalls
- Variations
- Closing: When to Reach for This