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Array Product Except Self

Best Single Trade in a Day

Best Trades With K Transactions and Fee

Closer-Stronger Bid Distance (Bidirectional): Min of Prev / Next Strictly-Higher Bid

Closest Trade Pair to Target Notional

Compact a Ring-Buffer of Ticks into Evenly-Bucketed Time Slices

Count K-Tick Windows With Every Quote Inside the Tolerance Band

Count of Strictly-Positive Net-Inflow K-Period Windows

Cumulative PnL Drawdown Alert: Sorted Indices Underwater Beyond Threshold

Cumulative PnL Zero-Crossings: Count Sign Flips of the Backtest Equity Curve

Cumulative Volume Snapshot

Cumulative VWAP at Each Tick

Days Until a Better PnL

Deduplicate a Replayed Tick Stream by (ts, exchange-seq), Latest-Ingest Wins

Downsample a Tick Stream into OHLCV Bars (Right-Closed)

Earliest K-Period Window Whose Cumulative Return Meets A Sum Target And Whose Worst Single Period Stays Above A Floor

Earliest K-Day Window Whose Population Variance Strictly Exceeds A Spike Threshold

Exponentially-Weighted Sharpe Ratio

RiskMetrics EWMA Volatility Forecast

EWMA Volatility Update

Rolling Historical Expected Shortfall (CVaR)

Find the Pivot Index of a P&L Stream

First Day Cumulative PnL Crosses Threshold

Forward-Fill Missing Minutes Within a Trading Session

Highest K-Day Range

Rolling Historical VaR Track

Idiosyncratic Volatility Factor — Rolling Residual Std After Market Beta

K-Day Momentum Hits

K-Day Rolling Mean Filter

Largest Volume Rectangle in a Histogram

Longest Contiguous Window of Volumes Within an Impact Budget

Longest Stable Trading Streak

Longest Trailing Window Whose Absolute-Return Sum Stays Within a Volatility Budget

Match Bid and Ask Snapshots

Maximum Profit Over Bounded-Drawdown Window

Max Sum of Fixed-Size Window

Maximum Concurrent Trades

Mean-Reversion Factor — Residualized Last-K Return

Merge Per-Day Bar Shards into a Sorted Timeseries

Merge K Sorted Trade Streams

Merge Two Trade Tapes

Min Cancels for Quote Stability

Min Replenishments to Avoid Stockout

Min-Stack with O(1) get_min

Misra-Gries (k-1)-Counter Heavy-Hitters Over a Trade-Tape Stream

Time-to-New-All-Time-High: First Future Index Strictly Above the Running Peak

Next Depth-Jump within a Forward Window: Bounded-Distance Ratio-Threshold Scan over a Best-Bid-Depth Tape

Next Greater Quote Timestamp

Next Smaller Element Index

Notional by Venue, Ranked

Lag-1 Sample Autocorrelation of a Time Series

Online Cumulative Bollinger Bands: Welford-Recurrence Band-Pair Stream

Online EWMA Covariance Pair — Cross-Asset Hedge-Ratio Building Block

Online EWMA Residual Stream — Surprise-vs-Prior Exponential-Weight Mean

Online EWMA Variance — Recency-Weighted Volatility Tracker

Running Mean and Mean Absolute Deviation

Online Median of Slippage

Online Running Excess Kurtosis via Welford-Style Fourth-Moment Recurrence

Online Running Sample Skewness via Welford-Style Third-Moment Recurrence

Online Streaming Mean, Variance, Skewness, and Excess Kurtosis (Welford-Pebay)

Online Z-Score Anomaly Flag

Online Z-Score Outlier Flagger: Welford-Cumulative Anomaly Detection on a Tick Stream

Optimal Cooldown Period Trades

Rolling Parametric VaR (Normal)

Peak Inventory Day After Batched Range-Update Trades

Prev-Stronger Bid Distance: Time Since the Last Strictly-Higher Bid Print

2D Range Sum via Prefix Table

Rank Strategies by Sharpe with Vol Tiebreak

Forward Recovery Distance: Days Until Cumulative Gain Clears Delta

Removing K Digits — Smallest Result

Rolling Beta — Strategy vs. Benchmark

Rolling Beta vs Benchmark

Rolling Pearson Correlation Between Two Series

Rolling Max-Min Spread

First-Update-After-Stale-Period Flags on a Quote-Update Timestamp Stream

Live Trade-Rate Count over a Half-Open Lookback Sliding Window

Longest Stable-Volatility Regime via Rolling Sample-Stddev Sliding Window

Minute-Bar Range Monitor via Dual-Deque Sliding Max-Minus-Min

Rolling Z-Score Anomaly Flags

Running Maximum Drawdown of a Streamed Log-Return NAV Path

Running Min and Max of a Stream

Running Cumulative-History Pearson Correlation via Welford-Style Co-Moment Recurrence

P-Square (P²) Streaming Quantile Estimator

Running Unbroken-Bid Stack Sum: Cumulative Support of Still-Standing Prior Bids

Sector-Day Return Cube: Batched Rectangular Range Sums

Session-Window Aggregation — Gap-Driven Boundaries

Shortest Contiguous Window Whose Absolute-Return Sum First Reaches a Stress-Budget Target

Shortest Window Containing K Magnitude Spikes in a Return Stream

Sliding Window Max of Quotes

Sliding-Window Mean — Fixed-Count Window with O(1) Eviction

Span of Higher Highs

Online Stock Span

Total Uniform-Fill Shares across Every Order-Book Level Range

Subarray Sum Equals K

Subranges Above Return Threshold

Aggregate Bottleneck Bid-Depth across All Contiguous Price-Band Sweeps (Depth-Uniformity Score)

Sum of Subarray Minimum P&Ls

Tick Buffer — Binary-Search Lookup and Range Scan by Timestamp

Top K Liquid Tickers

Top K PnL Days So Far

Trailing High-Watermark Span: Per-Tick Consolidation Length on a Synthetic Tape

Trailing 12-1 Momentum Factor (Skip Last Month)

Trapping Volume Between Local-Max Quotes

Tumbling-Window Aggregation — Sparse Per-Bucket Stats

Unique Tickers In Session

Count and Timestamp VaR Breaches

Walk-Forward Train/Test Splits with Embargo

Watermark-Driven Tumbling Windows with Late-Event Handling

Welford's Online Variance

Welford Warm-up-Trimmed Sample Variance — Stable Online Estimator on a Trailing Tail

Sliding-Window Argmin Offset: Per-Window Position of the Minimum Price Relative to the Window Left Edge

Tumbling Window Trigger Firing Policies (Early, On-Close, Speculative)

Rolling Hit-Rate of Strictly-Positive Returns over a Fixed-Size Window