How to Find Time Complexity (Step-by-Step)

for (let i = 0; i < n; i++) {
  console.log(i);
}

for (let i = 0; i < n; i++) {
  // constant work
}

for (let i = 0; i < n; i++) {
  for (let j = 0; j < n; j++) {
    // work
  }
}

for (let i = 0; i < n; i++) {}
for (let j = 0; j < n; j++) {}

while (n > 1) {
  n = n / 2;
}

function fun(n) {
  if (n <= 1) return;
  fun(n - 1);
}

function fib(n) {
  if (n <= 1) return n;
  return fib(n - 1) + fib(n - 2);
}

O(n² + n + 10) + O(n²)

O(5n)  O(n)
O(1000) ’ O(1)