Data Update

Task/Arithmetic-derivative/Rust/arithmetic-derivative.rust

@@ -0,0 +1,25 @@
+use prime_factorization::Factorization;
+
+fn d(n: i128) -> i128 {
+    if n < 0 {
+        return -(d(-n));
+    } else if n < 2 {
+        return 0;
+    } else {
+        let fpairs = Factorization::run(n as u128).prime_factor_repr();
+        if fpairs.len() == 1 && fpairs[0].1 == 1 {
+            return 1;
+        }
+        return fpairs.iter().fold(0_i128, |p, q| p + n * (q.1 as i128) / (q.0 as i128));
+    }
+}
+
+fn main() {
+    for n in -99..101 {
+        print!("{:5}{}", d(n), { if n % 10 == 0 { "\n" } else {""} });
+    }
+    println!();
+    for m in 1..21 {
+        println!("(D for 10 ^ {}) divided by 7 is {}", m, d(10_i128.pow(m)) / 7)
+    }
+}