Patterns

Single pass through input making a per-element decision; no auxiliary data structure

When to useFind max/min, count satisfying condition, in-place transform, simple aggregations that don't need a Map/Set/Stack

iterative

Simulate Print Queue

simulate_print_queue

Time Needed to Buy Tickets

time_needed_to_buy_tickets

Smallest Integer Satisfying the Rule

google_oa_smallest_integer

amazon_oa_winning_sequence

Candyhard

candy · no slots

Car Poolingmedium

car_pooling · no slots

INITIALIZE

accumulator / running tracker / result variable

const result = []; let time = 0;

let time = 0;

const result = digits.split('');

const n = s.length; if (n < 2) return ''; const chars = s.split('');

if (n < 3) return 0; let total = 0; let run = 1;

if (m < 2) return [];
const result = [];

—

TRAVERSE

for each element (or index) in input

for (const pages of jobs) {

for (let i = 0; i < tickets.length; i++) {

for (let i = 0; i < result.length; i++) {

for (let i = 0; i < Math.floor(n / 2); i++) {

for (let i = 1; i < n - 1; i++) {

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

—

[PROCESS]

per-element decision: update accumulator

  time += pages;
  result.push(time);

  const cap = i <= k ? tickets[k] : tickets[k] - 1;
  time += Math.min(tickets[i], cap);

  if (result[i] !== '?') continue;
  for (const d of '123456789') {
    const left = i > 0 ? result[i - 1] : '';
    const right = i < result.length - 1 ? result[i + 1] : '';
    if (d !== left && d !== right) { result[i] = d; break; }
  }

  if (chars[i] !== 'a') { chars[i] = 'a'; return chars.join(''); }

  if (same diff) { run++; total += run - 1; } else { run = 1; }

  if (i === 0) result.push(1);
  else if (i === 1) result.push(2);
  else {
    const candidate = result[i - 1] + 1;
    if (candidate <= m && candidate !== result[i - 2]) result.push(candidate);
    else result.push(result[i - 2]);
  }

—

RETURN

return accumulator

return result;

return time;

return result.join('');

chars[n - 1] = 'b'; return chars.join('');

return total >= 1e9 ? -1 : total;

return result;

—