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README.md

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+# POWlib
+POWlib is a pure rust library for scrypt-based proof-of-work challenges.  
+It uses 32-byte long scrypt hash with following parameters: `log_n: 6, r: 64, p: 1`
+
+# Example usage
+To load an existing challenge: you may use `powlib::gen::POWChallenge { hash: [a 32-byte long hash], range: POWRange::new(min, max) }`  
+To generate a challenge, use this: `powlib::gen::POWChallenge::make(POWRange::new(min, max))`  
+To solve a challenge, use this: `challenge.solve_singlethread()`
+
+Threaded solve method is planned but if you want to implement your own, there is a chunked method for solving: `challenge.chunk_solve(min, max)`
+
+So, the simplest code would look like this:
+
+```rust
+
+use powlib::{self, gen::{POWRange, POWChallenge}};
+
+fn main() {
+    let challenge = POWChallenge::make(POWRange::new(0, 20480));
+    println!("{}", challenge.solve_singlethread());
+}
+
+```