javascript example

Fibonacci sequence in JavaScript

Print the first Fibonacci numbers with an iterative loop — no recursion, no install.

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Keep the last two values and add them. Iteration stays fast and will not blow the stack on a longer list.

Change how many terms you print. If a run feels slow, shrink the count — the sandbox has a time limit.

function fibonacci(count) {
  const values = [];
  let a = 0;
  let b = 1;
  for (let i = 0; i < count; i++) {
    values.push(a);
    const next = a + b;
    a = b;
    b = next;
  }
  return values;
}

console.log(fibonacci(10).join(", "));