結果

問題 No.554 recurrence formula
ユーザー kitakitalilykitakitalily
提出日時 2019-03-30 18:04:28
言語 Java21
(openjdk 21)
結果
AC  
実行時間 58 ms / 2,000 ms
コード長 3,308 bytes
コンパイル時間 4,404 ms
コンパイル使用メモリ 81,248 KB
実行使用メモリ 37,048 KB
最終ジャッジ日時 2024-11-15 21:01:26
合計ジャッジ時間 5,847 ms
ジャッジサーバーID
（参考情報） 		judge4 / judge2
このコードへのチャレンジ
（要ログイン）

テストケース

テストケース表示
入力 結果 実行時間
実行使用メモリ
testcase_00 AC 48 ms
36,516 KB
testcase_01 AC 51 ms
36,992 KB
testcase_02 AC 49 ms
36,724 KB
testcase_03 AC 50 ms
36,996 KB
testcase_04 AC 50 ms
36,712 KB
testcase_05 AC 50 ms
37,028 KB
testcase_06 AC 49 ms
36,864 KB
testcase_07 AC 49 ms
36,836 KB
testcase_08 AC 48 ms
36,788 KB
testcase_09 AC 49 ms
37,012 KB
testcase_10 AC 49 ms
36,740 KB
testcase_11 AC 51 ms
36,768 KB
testcase_12 AC 50 ms
37,048 KB
testcase_13 AC 52 ms
36,524 KB
testcase_14 AC 51 ms
36,876 KB
testcase_15 AC 51 ms
36,940 KB
testcase_16 AC 50 ms
36,844 KB
testcase_17 AC 50 ms
36,508 KB
testcase_18 AC 52 ms
37,044 KB
testcase_19 AC 58 ms
36,964 KB
testcase_20 AC 58 ms
36,756 KB
権限があれば一括ダウンロードができます

ソースコード

diff # 

package contest170811;
import java.io.ByteArrayInputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.PrintWriter;
import java.util.Arrays;
import java.util.InputMismatchException;

public class C {
	InputStream is;
	PrintWriter out;
	String INPUT = "";
	
	void solve()
	{
		long[] sum = new long[2];
		int n = ni();
		int mod = 1000000007;
		if(n == 1){
			out.println(1);
			return;
		}
		sum[1] = 1;
		for(int i = 2;i <= n;i++){
			long val = i * sum[i&1^1] % mod;
			if(i == n){
				out.println(val);
				return;
			}
			sum[i&1] += val;
			sum[i&1] %= mod;
		}
	}
	
	void run() throws Exception
	{
		is = INPUT.isEmpty() ? System.in : new ByteArrayInputStream(INPUT.getBytes());
		out = new PrintWriter(System.out);
		
		long s = System.currentTimeMillis();
		solve();
		out.flush();
		if(!INPUT.isEmpty())tr(System.currentTimeMillis()-s+"ms");
//		Thread t = new Thread(null, null, "~", Runtime.getRuntime().maxMemory()){
//			@Override
//			public void run() {
//				long s = System.currentTimeMillis();
//				solve();
//				out.flush();
//				if(!INPUT.isEmpty())tr(System.currentTimeMillis()-s+"ms");
//			}
//		};
//		t.start();
//		t.join();
	}
	
	public static void main(String[] args) throws Exception { new C().run(); }
	
	private byte[] inbuf = new byte[1024];
	public int lenbuf = 0, ptrbuf = 0;
	
	private int readByte()
	{
		if(lenbuf == -1)throw new InputMismatchException();
		if(ptrbuf >= lenbuf){
			ptrbuf = 0;
			try { lenbuf = is.read(inbuf); } catch (IOException e) { throw new InputMismatchException(); }
			if(lenbuf <= 0)return -1;
		}
		return inbuf[ptrbuf++];
	}
	
	private boolean isSpaceChar(int c) { return !(c >= 33 && c <= 126); }
	private int skip() { int b; while((b = readByte()) != -1 && isSpaceChar(b)); return b; }
	
	private double nd() { return Double.parseDouble(ns()); }
	private char nc() { return (char)skip(); }
	
	private String ns()
	{
		int b = skip();
		StringBuilder sb = new StringBuilder();
		while(!(isSpaceChar(b))){ // when nextLine, (isSpaceChar(b) && b != ' ')
			sb.appendCodePoint(b);
			b = readByte();
		}
		return sb.toString();
	}
	
	private char[] ns(int n)
	{
		char[] buf = new char[n];
		int b = skip(), p = 0;
		while(p < n && !(isSpaceChar(b))){
			buf[p++] = (char)b;
			b = readByte();
		}
		return n == p ? buf : Arrays.copyOf(buf, p);
	}
	
	private int[] na(int n)
	{
		int[] a = new int[n];
		for(int i = 0;i < n;i++)a[i] = ni();
		return a;
	}
	
	private long[] nal(int n)
	{
		long[] a = new long[n];
		for(int i = 0;i < n;i++)a[i] = nl();
		return a;
	}
	
	private char[][] nm(int n, int m) {
		char[][] map = new char[n][];
		for(int i = 0;i < n;i++)map[i] = ns(m);
		return map;
	}
	
	private int[][] nmi(int n, int m) {
		int[][] map = new int[n][];
		for(int i = 0;i < n;i++)map[i] = na(m);
		return map;
	}
	
	private int ni() { return (int)nl(); }
	
	private long nl()
	{
		long num = 0;
		int b;
		boolean minus = false;
		while((b = readByte()) != -1 && !((b >= '0' && b <= '9') || b == '-'));
		if(b == '-'){
			minus = true;
			b = readByte();
		}
		
		while(true){
			if(b >= '0' && b <= '9'){
				num = num * 10 + (b - '0');
			}else{
				return minus ? -num : num;
			}
			b = readByte();
		}
	}
	
	private static void tr(Object... o) { System.out.println(Arrays.deepToString(o)); }
}
0