Understand how dynamic programming solves complex problems by breaking them into simpler subproblems
Classic recursive problem with overlapping subproblems
Optimization problem with capacity constraints
Finding longest sequence common to both strings
Minimizing scalar multiplications
Finding minimum coins for a given amount
| n | 0 | 1 | 2 | 3 | 4 | 5 | 6 |
|---|---|---|---|---|---|---|---|
| fib(n) | 0 | 1 | 1 | 2 | 3 | 5 | 8 |
Calculating fib(6) by adding previously computed values fib(5)=5 and fib(4)=3.
def fibonacci(n, memo={}):
if n in memo:
return memo[n]
if n <= 1:
return n
memo[n] = fibonacci(n-1, memo) + fibonacci(n-2, memo)
return memo[n]
The Fibonacci sequence exhibits optimal substructure and overlapping subproblems, making it ideal for dynamic programming optimization.
Without memoization, the naive recursive approach has exponential time complexity \( O(\phi^n) \) where \( \phi \) is the golden ratio. Memoization reduces this to linear time by storing previously computed values.