// floor(a ^ (1 / k)) fn kth_root(a: u64, k: u64) -> u64 { assert!(k > 0); if a == 0 { return 0; } if k >= 64 { return 1; } if k == 1 { return a; } let valid = |x: u64| -> bool { let mut t = x; for _ in 1..k { let (val, ok) = t.overflowing_mul(x); if !(!ok && val <= a) { return false; } t = val; } true }; let mut ok = 1; let mut ng = 2; while valid(ng) { ok = ng; ng *= 2; } while ng - ok > 1 { let mid = ok + (ng - ok) / 2; if valid(mid) { ok = mid; } else { ng = mid; } } ok } // ---------- begin input macro ---------- // reference: https://qiita.com/tanakh/items/0ba42c7ca36cd29d0ac8 macro_rules! input { (source = $s:expr, $($r:tt)*) => { let mut iter = $s.split_whitespace(); input_inner!{iter, $($r)*} }; ($($r:tt)*) => { let s = { use std::io::Read; let mut s = String::new(); std::io::stdin().read_to_string(&mut s).unwrap(); s }; let mut iter = s.split_whitespace(); input_inner!{iter, $($r)*} }; } macro_rules! input_inner { ($iter:expr) => {}; ($iter:expr, ) => {}; ($iter:expr, $var:ident : $t:tt $($r:tt)*) => { let $var = read_value!($iter, $t); input_inner!{$iter $($r)*} }; } macro_rules! read_value { ($iter:expr, ( $($t:tt),* )) => { ( $(read_value!($iter, $t)),* ) }; ($iter:expr, [ $t:tt ; $len:expr ]) => { (0..$len).map(|_| read_value!($iter, $t)).collect::>() }; ($iter:expr, chars) => { read_value!($iter, String).chars().collect::>() }; ($iter:expr, bytes) => { read_value!($iter, String).bytes().collect::>() }; ($iter:expr, usize1) => { read_value!($iter, usize) - 1 }; ($iter:expr, $t:ty) => { $iter.next().unwrap().parse::<$t>().expect("Parse error") }; } // ---------- end input macro ---------- use std::io::Write; use std::collections::*; type Map = BTreeMap; type Set = BTreeSet; type Deque = VecDeque; fn run() { input! { n: u64, } let k = kth_root(n, 3); if k.pow(3) == n { println!("Yes"); } else { println!("No"); } } fn main() { run(); }