complete 2083.rs 2530.rs 2721.rs 4128.rs 5584.rs 7512.rs 21519.rs 21964.rs 22862.rs 22973.rs 24123.rs 26993.rs 27514.rs 33849.rs

storage/zeta/rs/completed/2721.rs

@@ -0,0 +1,24 @@
+use std::io::{read_to_string, stdin};
+
+fn W(n: usize) -> usize {
+    // W(1) = 1 * T(2) = 3
+    // W(2) = 1 * T(2) + 2 * T(3) = 12 + 3 = 15
+    // W(n + 1) - W(n) = n * T(n + 1) = n * (n + 1) * (n + 2) / 2
+    if n == 1 {
+        3
+    } else {
+        n * (n + 1) * (n + 2) / 2 + W(n - 1)
+    }
+}
+
+fn main() {
+    let temp = read_to_string(stdin()).unwrap();
+    let mut iter = temp
+        .split_ascii_whitespace()
+        .map(|x| x.parse::<usize>().unwrap());
+
+    (0..iter.next().unwrap()).for_each(|_| {
+        let n = iter.next().unwrap();
+        println!("{}", W(n));
+    });
+}