Python · Theory

Fibonacci

Theory

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Fibonacci

Fibonacci is a classic practice problem. State the rule, trace a tiny input, then code. Fibonacci: next = sum of last two. Second largest: watch duplicates. Hanoi: move n-1, biggest, n-1. Distance: sqrt((x2-x1)**2 + (y2-y1)**2).

For Fibonacci — say the output for one small n before you write the loop. That is the exam.

Fibonacci — output — [0, 1, 1, 2, 3, 5]. Real sequence, not dummy numbers.

Exam tip

Rule + one dry-run + then code.

Example

# Fibonacci
a, b = 0, 1
out = []
for _ in range(6):
    out.append(a)
    a, b = b, a + b
print(out)

Fibonacci — output: [0, 1, 1, 2, 3, 5]. Real sequence, not dummy numbers.

Short notes

DefFibonacci — know the rule.
RuleFibonacci — tiny trace first.
RememberFibonacci — edge cases (n=0, duplicates).

Python · Theory

Fibonacci

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Theory

106/268

Fibonacci

For Fibonacci — say the output for one small n before you write the loop. That is the exam.

Fibonacci — output — [0, 1, 1, 2, 3, 5]. Real sequence, not dummy numbers.

Exam tip

Rule + one dry-run + then code.

Example

# Fibonacci
a, b = 0, 1
out = []
for _ in range(6):
    out.append(a)
    a, b = b, a + b
print(out)

Fibonacci — output: [0, 1, 1, 2, 3, 5]. Real sequence, not dummy numbers.

Short notes

DefFibonacci — know the rule.
RuleFibonacci — tiny trace first.
RememberFibonacci — edge cases (n=0, duplicates).

Fibonacci

Example

Short notes

Questions

Fibonacci

Example

Short notes

Questions