Big O

{
  "asOf": "2026-10-11T20:19:38.657Z",
  "budgetSeconds": 1,
  "classes": [
    {
      "class": "O(1)",
      "feasibleWithinBudget": true,
      "largestNWithinBudget": null,
      "log10Operations": 0,
      "name": "constant",
      "operations": "1",
      "seconds": 1e-9,
      "time": "under a microsecond"
    },
    {
      "class": "O(log n)",
      "feasibleWithinBudget": true,
      "largestNWithinBudget": null,
      "log10Operations": 0.999,
      "name": "logarithmic",
      "operations": "10",
      "seconds": 9.965784284662073e-9,
      "time": "under a microsecond"
    }
  ],
  "degraded": false,
  "disclaimer": "Screening signal computed from the named public source. Not financial, legal or investment advice; provided as is. Verify at the source before acting.",
  "n": 1000,
  "notChecked": [
    "constant factors, caches, parallelism and memory: Big-O ignores them and real programs differ by 10x or more",
    "average versus worst case, and space complexity",
    "…1 more"
  ],
  "operationBudget": 1000000000,
  "opsPerSecond": 1000000000,
  "reasons": [
    "Operation counts are the class formula with constant 1 (log base 2), so they compare growth rates, not real run times.",
    "Largest n = the biggest input whose step count stays within the budget (budget seconds x ops per second)."
  ],
  "source": "computed locally",
  "summary": "n = 1,000 at 1.0e+9 ops/s: O(1), O(log n), O(n), O(n log n), O(n^2), O(n^3) fit in 1 s; too slow: O(2^n), O(n!).",
  "verdict": "SOME_INFEASIBLE"
}

# bash or zsh: see the payment challenge. Nothing is charged.
curl -sS -g -i 'https://data-calc.x402tookit.com/big-o?budgetSeconds=1&n=1000&opsPerSecond=1000000000'

# x402 v2 sends the challenge base64-encoded in the PAYMENT-REQUIRED header (v1 sends it in the body).
# To read the header:
curl -sS -g -o /dev/null -D - 'https://data-calc.x402tookit.com/big-o?budgetSeconds=1&n=1000&opsPerSecond=1000000000' \
  | grep -i '^payment-required:' | cut -d' ' -f2 | tr -d '\r' | base64 --decode

// npm i @x402/fetch @x402/evm viem
import { wrapFetchWithPayment, x402Client } from "@x402/fetch";
import { registerExactEvmScheme } from "@x402/evm/exact/client";
import { privateKeyToAccount } from "viem/accounts";

// Pays at most $0.02 per call.
const client = new x402Client().setSpendControls({ maxAmountPerPayment: "$0.02" });
registerExactEvmScheme(client, { signer: privateKeyToAccount(process.env.EVM_PRIVATE_KEY) });
const pay = wrapFetchWithPayment(fetch, client);

// Not sure it's safe to pay? ToolVet checks it first for $0.005. Pay for that from a separate
// client: this one is capped at $0.02 per payment. GET https://toolvet.app/api/v1/check?url=https%3A%2F%2Fdata-calc.x402tookit.com%2Fbig-o
const res = await pay("https://data-calc.x402tookit.com/big-o?budgetSeconds=1&n=1000&opsPerSecond=1000000000");
console.log(res.status, await res.text());

# pip install "x402[requests,evm]"
import os
from eth_account import Account
from x402 import x402ClientSync
from x402.http.clients import x402_requests
from x402.mechanisms.evm import EthAccountSigner
from x402.mechanisms.evm.exact.register import register_exact_evm_client

# Pays at most $0.02 per call.
client = x402ClientSync().set_spend_controls({"max_amount_per_payment": "$0.02"})
register_exact_evm_client(client, EthAccountSigner(Account.from_key(os.environ["EVM_PRIVATE_KEY"])))

with x402_requests(client) as session:
    res = session.get("https://data-calc.x402tookit.com/big-o?budgetSeconds=1&n=1000&opsPerSecond=1000000000")
    print(res.status_code, res.text)