complete 2921.rs

storage/zeta/rs/completed/2921.rs

@@ -0,0 +1,14 @@
+use std::io::{read_to_string, stdin};
+
+fn main() {
+    let temp = read_to_string(stdin()).unwrap();
+    let mut iter = temp
+        .split_ascii_whitespace()
+        .map(|x| x.parse::<usize>().unwrap());
+    let n = iter.next().unwrap();
+    let mut s = 0;
+    for i in 1..=n {
+        s += 3 * (i + 1) * i / 2;
+    }
+    println!("{}", s);
+}