Add hintfile analyzer

Cargo.toml

@@ -1,5 +1,5 @@
 [workspace]
-members = ["accumulator", "hintfile", "node"]
+members = ["accumulator", "analysis", "hintfile", "node"]
 default-members = ["accumulator"]
 resolver = "2"
 

analysis/Cargo.toml

@@ -0,0 +1,8 @@
+[package]
+name = "analysis"
+version = "0.1.0"
+edition = "2021"
+
+[dependencies]
+csv = "1.4.0"
+hintfile = { path = "../hintfile/" }

analysis/src/main.rs

@@ -0,0 +1,43 @@
+use std::fs::File;
+
+use hintfile::Hints;
+
+fn differentials(indexes: &[u64]) -> Vec<u64> {
+    indexes
+        .iter()
+        .zip(indexes.iter().skip(1))
+        .map(|(a, b)| b - a)
+        .collect()
+}
+
+fn average(diffs: &[u64]) -> f64 {
+    let sum = diffs.iter().sum::<u64>() as f64;
+    if !diffs.is_empty() {
+        return sum / diffs.len() as f64;
+    }
+    0.
+}
+
+fn main() {
+    let path = std::env::args()
+        .nth(1)
+        .expect("Usage: </path/to/hintsfile>");
+    let file = File::open(path).unwrap();
+    let mut hints = Hints::from_file(file);
+    let csv = File::create("./results.csv").unwrap();
+    let mut wtr = csv::Writer::from_writer(csv);
+    for height in 1..=hints.stop_height() {
+        let unspents = hints.get_indexes(height);
+        let max_unspent = unspents.iter().max().unwrap_or(&0);
+        let diffs = differentials(&unspents);
+        let average_diff = average(&diffs);
+        println!("Block height: {height}; average diff: {average_diff}; max index: {max_unspent}; diffs: {diffs:?}");
+        wtr.write_record(vec![
+            height.to_string(),
+            average_diff.to_string(),
+            max_unspent.to_string(),
+        ])
+        .unwrap();
+        // std::thread::sleep(Duration::from_millis(500));
+    }
+}