add abc400c.rs

rchaser53 · rchaser53 · commit 773a6aee2129 · 2025-04-07T20:57:38.000+09:00
diff --git a/src/abc/abc400c.rs b/src/abc/abc400c.rs
@@ -0,0 +1,26 @@
+
+use proconio::input;
+use proconio::marker::*;
+use std::marker::PhantomData;
+use std::cmp::*;
+use std::collections::*;
+use num_integer::sqrt;
+
+fn main() {
+  input! {
+    n:usize,
+  }
+
+  let mut result = 0;
+  let mut a_pow = 1;
+  for _ in 1..=60 {
+    a_pow *= 2;
+    if n < a_pow {
+      continue
+    }
+    let b = sqrt(n as u64 / a_pow as u64);
+    result += (b+1)/2;
+  }
+  println!("{result}");
+  
+}
