package backjoon; import java.io.BufferedReader; import java.io.IOException; import java.io.InputStreamReader; // https://www.acmicpc.net/problem/2292 // 벌집 public class _2292 { public static void main(String[] args) throws IOException { BufferedReader br = new BufferedReader(new InputStreamReader(System.in)); // memory 11448 runtime 76 int N = Integer.parseInt(br.readLine()); int cnt = 1; int range = 2; // ë‹¤ìŒ ì¤„ë¡œ 넘어가는 ë²Œì§‘ì˜ ë²”ìœ„ (최솟값 기준) if (N == 1) { System.out.print(1); } else { while (range <= N) { // ë°©ì˜ ë²”ìœ„ëŠ” 6ì˜ ë°°ìˆ˜ë¼ì„œ (6 * cnt)ìž„ range = range + (6 * cnt); cnt++; } System.out.print(cnt); } } } /* input 13 output 3 */