Data commit

Task/Fusc-sequence/Rust/fusc-sequence.rust

@@ -0,0 +1,36 @@
+fn fusc_sequence() -> impl std::iter::Iterator<Item = u32> {
+    let mut sequence = vec![0, 1];
+    let mut n = 0;
+    std::iter::from_fn(move || {
+        if n > 1 {
+            sequence.push(match n % 2 {
+                0 => sequence[n / 2],
+                _ => sequence[(n - 1) / 2] + sequence[(n + 1) / 2],
+            });
+        }
+        let result = sequence[n];
+        n += 1;
+        Some(result)
+    })
+}
+
+fn main() {
+    println!("First 61 fusc numbers:");
+    for n in fusc_sequence().take(61) {
+        print!("{} ", n)
+    }
+    println!();
+
+    let limit = 1000000000;
+    println!(
+        "Fusc numbers up to {} that are longer than any previous one:",
+        limit
+    );
+    let mut max = 0;
+    for (index, n) in fusc_sequence().take(limit).enumerate() {
+        if n >= max {
+            max = std::cmp::max(10, max * 10);
+            println!("index = {}, fusc number = {}", index, n);
+        }
+    }
+}