結果

問題 No.505 カードの数式2
コンテスト
ユーザー Grenache
提出日時 2017-04-21 22:59:50
言語 Java
(openjdk 23)
結果
AC  
実行時間 55 ms / 2,000 ms
コード長 5,275 bytes
コンパイル時間 3,749 ms
コンパイル使用メモリ 79,824 KB
実行使用メモリ 50,580 KB
最終ジャッジ日時 2024-11-14 07:18:46
合計ジャッジ時間 6,387 ms
ジャッジサーバーID
（参考情報） 		judge5 / judge1
このコードへのチャレンジ
（要ログイン）
ファイルパターン 結果
sample AC * 3
other AC * 29
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 # 

import java.io.*;
import java.util.*;


public class Main_yukicoder505 {

	private static Scanner sc;
	private static Printer pr;

	private static void solve() {
		int n = sc.nextInt();

		int[] a = new int[n];
		for (int i = 0; i < n; i++) {
			a[i] = sc.nextInt();
		}

		long[] dpmax = new long[n];
		long[] dpmin = new long[n];
		Arrays.fill(dpmax, Long.MIN_VALUE);
		Arrays.fill(dpmin, Long.MAX_VALUE);
		dpmax[0] = a[0];
		dpmin[0] = a[0];
		for (int i = 1; i < n; i++) {
			for (int j = 0; j < 4; j++) {
				if (j == 0) {
					dpmax[i] = Math.max(dpmax[i], dpmax[i - 1] + a[i]);
					dpmax[i] = Math.max(dpmax[i], dpmin[i - 1] + a[i]);
					dpmin[i] = Math.min(dpmin[i], dpmax[i - 1] + a[i]);
					dpmin[i] = Math.min(dpmin[i], dpmin[i - 1] + a[i]);
				} else if (j == 1) {
					dpmax[i] = Math.max(dpmax[i], dpmax[i - 1] - a[i]);
					dpmax[i] = Math.max(dpmax[i], dpmin[i - 1] - a[i]);
					dpmin[i] = Math.min(dpmin[i], dpmax[i - 1] - a[i]);
					dpmin[i] = Math.min(dpmin[i], dpmin[i - 1] - a[i]);
				} else if (j == 2) {
					dpmax[i] = Math.max(dpmax[i], dpmax[i - 1] * a[i]);
					dpmax[i] = Math.max(dpmax[i], dpmin[i - 1] * a[i]);
					dpmin[i] = Math.min(dpmin[i], dpmax[i - 1] * a[i]);
					dpmin[i] = Math.min(dpmin[i], dpmin[i - 1] * a[i]);
				} else if (j == 3 && a[i] != 0) {
					dpmax[i] = Math.max(dpmax[i], dpmax[i - 1] / a[i]);
					dpmax[i] = Math.max(dpmax[i], dpmin[i - 1] / a[i]);
					dpmin[i] = Math.min(dpmin[i], dpmax[i - 1] / a[i]);
					dpmin[i] = Math.min(dpmin[i], dpmin[i - 1] / a[i]);
				}
			}
		}

		pr.println(dpmax[n - 1]);
	}

	// ---------------------------------------------------
	public static void main(String[] args) {
		sc = new Scanner(System.in);
		pr = new Printer(System.out);

		solve();

		pr.close();
		sc.close();
	}

	@SuppressWarnings("unused")
	private static class Scanner {
		BufferedReader br;

		Scanner (InputStream in) {
			br = new BufferedReader(new InputStreamReader(in));
		}

		private boolean isPrintable(int ch) {
			return ch >= '!' && ch <= '~';
		}

		private boolean isCRLF(int ch) {
			return ch == '\n' || ch == '\r' || ch == -1;
		}

		private int nextPrintable() {
			try {
				int ch;
				while (!isPrintable(ch = br.read())) {
					if (ch == -1) {
						throw new NoSuchElementException();
					}
				}

				return ch;
			} catch (IOException e) {
				throw new NoSuchElementException();
			}
		}

		String next() {
			try {
				int ch = nextPrintable();
				StringBuilder sb = new StringBuilder();
				do {
					sb.appendCodePoint(ch);
				} while (isPrintable(ch = br.read()));

				return sb.toString();
			} catch (IOException e) {
				throw new NoSuchElementException();
			}
		}

		int nextInt() {
			try {
				// parseInt from Integer.parseInt()
				boolean negative = false;
				int res = 0;
				int limit = -Integer.MAX_VALUE;
				int radix = 10;

				int fc = nextPrintable();
				if (fc < '0') {
					if (fc == '-') {
						negative = true;
						limit = Integer.MIN_VALUE;
					} else if (fc != '+') {
						throw new NumberFormatException();
					}
					fc = br.read();
				}
				int multmin = limit / radix;

				int ch = fc;
				do {
					int digit = ch - '0';
					if (digit < 0 || digit >= radix) {
						throw new NumberFormatException();
					}
					if (res < multmin) {
						throw new NumberFormatException();
					}
					res *= radix;
					if (res < limit + digit) {
						throw new NumberFormatException();
					}
					res -= digit;

				} while (isPrintable(ch = br.read()));

				return negative ? res : -res;
			} catch (IOException e) {
				throw new NoSuchElementException();
			}
		}

		long nextLong() {
			try {
				// parseLong from Long.parseLong()
				boolean negative = false;
				long res = 0;
				long limit = -Long.MAX_VALUE;
				int radix = 10;

				int fc = nextPrintable();
				if (fc < '0') {
					if (fc == '-') {
						negative = true;
						limit = Long.MIN_VALUE;
					} else if (fc != '+') {
						throw new NumberFormatException();
					}
					fc = br.read();
				}
				long multmin = limit / radix;

				int ch = fc;
				do {
					int digit = ch - '0';
					if (digit < 0 || digit >= radix) {
						throw new NumberFormatException();
					}
					if (res < multmin) {
						throw new NumberFormatException();
					}
					res *= radix;
					if (res < limit + digit) {
						throw new NumberFormatException();
					}
					res -= digit;

				} while (isPrintable(ch = br.read()));

				return negative ? res : -res;
			} catch (IOException e) {
				throw new NoSuchElementException();
			}
		}

		float nextFloat() {
			return Float.parseFloat(next());
		}

		double nextDouble() {
			return Double.parseDouble(next());
		}

		String nextLine() {
			try {
				int ch;
				while (isCRLF(ch = br.read())) {
					if (ch == -1) {
						throw new NoSuchElementException();
					}
				}
				StringBuilder sb = new StringBuilder();
				do {
					sb.appendCodePoint(ch);
				} while (!isCRLF(ch = br.read()));

				return sb.toString();
			} catch (IOException e) {
				throw new NoSuchElementException();
			}
		}

		void close() {
			try {
				br.close();
			} catch (IOException e) {
//				throw new NoSuchElementException();
			}
		}
	}

	private static class Printer extends PrintWriter {
		Printer(PrintStream out) {
			super(out);
		}
	}
}
0