# diffsquare
[](https://crates.io/crates/diffsquare)
[](https://crates.io/crates/diffsquare)
[](https://docs.rs/diffsquare)
[](./LICENSE)
---
## From the Author
Created by [Abhrankan Chakrabarti](https://github.com/Abhrankan-Chakrabarti), this project implements an efficient version of Fermat’s Difference of Squares method for factoring large integers. Written in Rust, it leverages the [`malachite`](https://docs.rs/malachite/) crate for high-performance arbitrary-precision arithmetic.
---
## Recent Update – v0.8.0
🚀 **New in v0.8.0:**
* ✅ **Improved piped input support**
* Automatically detects when input is piped (non-interactive stdin).
* Gracefully reads multi-line numbers split with backslashes (e.g., from `bc`).
* Allows seamless integration with tools like `bc`, `openssl`, etc.
* Fully compatible with all output modes (`--json`, `--csv`, `--quiet`, `--time-only`).
---
## Key Features
`diffsquare` is a fast and lightweight CLI utility for factoring large integers using Fermat’s Difference of Squares method.
* Efficient Fermat's Difference of Squares factorization.
* Parallelized using [`rayon`](https://docs.rs/rayon) for faster factorization on multi-core systems (since v0.5.0).
* Optional file input for batch factorization (`--input`) (new in v0.7.0).
* Optional file output with `--output` to save results (since v0.6.0).
* Control thread count for batch processing with `--threads` (new in v0.7.0).
* Progress bar for file and stdin batch input (new in v0.7.0).
* Optional `--timeout N` to limit maximum time per factorization in milliseconds (since v0.6.1).
* CSV output support via `--csv` flag (since v0.6.1).
* JSON output mode (`--json`) for scripting and automation (since v0.3.0).
* Quiet mode (`-q`) disables prompts and hides intermediate output — ideal for scripting.
* `--time-only` flag for showing only execution time — useful for benchmarking (since v0.3.1).
* Batch factorization via `--stdin` (since v0.4.0).
* Support for decimal, hexadecimal, and scientific notation input.
* Command-line interface with interactive fallback.
* Optional control over iteration starting point (`--iter`) and precision (`--prec`).
* Scientific notation used in verbose mode for large integer readability.
* Execution time displayed after successful factorization.
> GitHub Repository: [`diffsquare`](https://github.com/Abhrankan-Chakrabarti/diffsquare)
---
## Installation
Install via Cargo:
```bash
cargo install diffsquare
```
Ensure `$HOME/.cargo/bin` is in your `PATH`:
```bash
export PATH="$HOME/.cargo/bin:$PATH"
```
---
## Build Instructions
To build from source manually:
```bash
git clone https://github.com/Abhrankan-Chakrabarti/diffsquare.git
cd diffsquare
cargo build --release
```
---
## 🔧 Usage Examples
Run `diffsquare` interactively or use flags for automation:
```bash
# 🔹 Fully interactive: prompts for modulus
diffsquare
# 🔹 Provide a decimal modulus
diffsquare -n 179769313486231590772930519078902473361797697894230657273430081157732675805505620686985379449212982959585501387537164015710139858647833778606925583497541085196591615128057575940752635007475935288710823649949940771895617054361149474865046711015101563940680527540071584560878577663743040086340742855278549092581
# 🔹 Provide a hexadecimal modulus
diffsquare -n 0xDEADBEEFCAFEBABE1234567890
# 🔹 Specify starting iteration
diffsquare -n 0xC0FFEE123456789 -i 1000000
# 🔹 Use custom precision for verbose scientific output
diffsquare -n 0xABCD1234 -p 30
# 🔹 Quiet mode, suppress intermediate output
diffsquare -n 0xCAFED00D1234 -q
# 🔹 JSON output for scripting
diffsquare -n 0xC0FFEE123456789 --json
# 🔹 Show only execution time (for benchmarking)
diffsquare -n 0xCAFED00D1234 --time-only
# 🔹 Factor 2^32 + 1 (Fermat number F5) from piped input
# 🔹 Batch factorization from stdin
echo -e "2761929023323646159\n3189046231347719467" | diffsquare --stdin
# 🔹 Batch factorization from file input
diffsquare --input numbers.txt
# 🔹 Batch with threads and JSON output
diffsquare --input numbers.txt --threads 4 --json
# 🔹 Batch with CSV output and save to file
diffsquare --input numbers.txt --csv --output results.csv
```
---
### Command-Line Flags
| `-n` | `--mod` | Number to factor (supports `0x` for hex or scientific notation) |
| `-i` | `--iter` | Starting iteration value |
| `-p` | `--prec` | Precision for verbose scientific output |
| `-q` | `--quiet` | Suppress prompts and intermediate output |
| | `--json` | Output result in JSON format |
| | `--csv` | Output result as CSV |
| | `--time-only` | Show only execution time |
| | `--stdin` | Read newline-separated input from stdin |
| | `--input` | Read newline-separated input from file |
| | `--threads` | Number of threads for batch factorization (`--stdin` / `--input`) (default: logical CPUs) |
| | `--output` | Output results to file |
| | `--timeout` | Timeout in milliseconds for each factorization |
| `-h` | `--help` | Show usage help |
| `-v` | `--version` | Show version |
---
## Tags
**Tags**
`#RustLang` `#NumberTheory` `#OpenSource` `#BigInteger` `#Cryptography` `#Fermat` `#AbhrankanChakrabarti` `#Malachite`