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How to Calculate Fibonacci with Dynamic Programming Caching

Here is how to calculate fibonacci with dynamic programming caching.
Run the program here: https://repl.it/@VinitKhandelwal/fibonacci-dynamic-programming
cal = 0
def slowFibonacci(n):
global cal
cal += 1
if n<2:
return n
return slowFibonacci(n-1) + slowFibonacci(n-2)

cal2 = 0
cache = {}
def fastFibonacci(n):
global cache, cal2
if n in cache:
return cache[n]
else:
cal2 += 1
if n<2:
return n
cache[n] = fastFibonacci(n-1) + fastFibonacci(n-2)
return cache[n]

print(f"Fibonacci without caching {slowFibonacci(30)}")
print(f"Calculated {cal} times")
print(f"Fibonacci without caching {fastFibonacci(30)}")
print(f"Calculated {cal2} times")
OUTPUT
Fibonacci without caching 832040
Calculated 2692537 times
Fibonacci without caching 832040
Calculated 32 times

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