Solve the market. One problem at a time.

Forty-eight problems on the math the workbench actually runs — pricing, risk, labels without lookahead, sizing. Your Python runs for real, in your browser, and the server grades it against hidden cases to six decimal places. Nothing at stake but your streak.

problems

tracks

real risk

paper only · educational · not advice

Problems48 of 48

status	#	title	track	difficulty	acceptance	est	open
○	01	Black-Scholes call price★	Finance	easy	—	15 min	solve →
○	02	Put-call parity check	Finance	easy	—	10 min	solve →
○	03	Implied volatility by bisection	Finance	medium	—	25 min	solve →
○	04	Bond price & duration	Finance	easy	—	15 min	solve →
○	05	CAGR from an equity curve	Finance	easy	—	10 min	solve →
○	06	PV of a cash-flow ladder	Finance	easy	—	10 min	solve →
○	07	Greeks by finite difference	Finance	medium	—	25 min	solve →
○	08	Binomial-tree American put	Finance	hard	—	40 min	solve →
○	09	Covered-call payoff table	Finance	easy	—	15 min	solve →
○	10	Max drawdown	Finance	easy	—	10 min	solve →
○	11	Sharpe ratio, annualised★	Quant	easy	—	15 min	solve →
○	12	Rolling z-score	Quant	easy	—	15 min	solve →
○	13	Hurst exponent by R/S	Quant	hard	—	40 min	solve →
○	14	Kalman filter for a price level	Quant	hard	—	40 min	solve →
○	15	Monte Carlo VaR	Quant	medium	—	25 min	solve →
○	16	Bollinger bands	Quant	easy	—	10 min	solve →
○	17	Half-life of mean reversion	Quant	medium	—	25 min	solve →
○	18	Pairs spread & cointegrationPro	Quant	hard	—	45 min	solve →
○	19	Heston Monte Carlo pricerPro	Quant	hard	—	45 min	solve →
○	20	Linear-regression channel	Quant	medium	—	20 min	solve →
○	21	Triple-barrier labels★	ML	medium	—	30 min	solve →
○	22	Purged & embargoed K-fold	ML	medium	—	30 min	solve →
○	23	Walk-forward folds	ML	medium	—	25 min	solve →
○	24	Feature matrix: RSI, MACD, returns	ML	easy	—	20 min	solve →
○	25	Cross-sectional rank of 34 tickers	ML	medium	—	25 min	solve →
○	26	Quantile outputs → signal	ML	medium	—	20 min	solve →
○	27	Regime split by VIX median	ML	easy	—	15 min	solve →
○	28	Out-of-fold stacking featuresPower · coming soon	ML	hard	—	40 min	solve →
○	29	Calibrate classifier probabilitiesPower · coming soon	ML	hard	—	35 min	solve →
○	30	Normal CDF, Abramowitz–Stegun	Maths	easy	—	15 min	solve →
○	31	Log vs simple returns	Maths	easy	—	10 min	solve →
○	32	GBM path	Maths	easy	—	15 min	solve →
○	33	Cholesky for correlated shocks	Maths	hard	—	40 min	solve →
○	34	Newton's method root	Maths	medium	—	20 min	solve →
○	35	Portfolio variance	Maths	easy	—	10 min	solve →
○	36	Barrier-touch probabilityPro	Maths	hard	—	35 min	solve →
○	37	Expected value of a bet	Maths	easy	—	10 min	solve →
○	38	Autocorrelation at lag k	Maths	medium	—	20 min	solve →
○	39	VWAP★	Trading	easy	—	15 min	solve →
○	40	Kelly fraction★	Trading	easy	—	15 min	solve →
○	41	SMA crossover signals	Trading	easy	—	15 min	solve →
○	42	Donchian breakout	Trading	easy	—	15 min	solve →
○	43	Position size from stop distance	Trading	easy	—	10 min	solve →
○	44	Long-only backtest with costs	Trading	medium	—	30 min	solve →
○	45	Order-book mid & micro-price	Trading	medium	—	20 min	solve →
○	46	Drawdown-aware kill switch	Trading	medium	—	20 min	solve →
○	47	Wheel cash-flow ledger	Trading	medium	—	30 min	solve →
○	48	Theta bleed to expiry	Trading	medium	—	20 min	solve →

acceptance = accepted ÷ submitted, from real submissions · "—" until a problem has 5paper only · educational · not advice