結果

問題 No.843 Triple Primes
ユーザー OlandOland
提出日時 2019-06-28 22:32:04
言語 Java21
(openjdk 21)
結果
AC  
実行時間 85 ms / 2,000 ms
コード長 4,472 bytes
コンパイル時間 2,724 ms
コンパイル使用メモリ 81,320 KB
実行使用メモリ 54,264 KB
最終ジャッジ日時 2023-10-19 17:49:11
合計ジャッジ時間 7,261 ms
ジャッジサーバーID
（参考情報） 		judge15 / judge12
このコードへのチャレンジ
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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 56 ms
52,584 KB
testcase_01 AC 78 ms
53,704 KB
testcase_02 AC 57 ms
53,676 KB
testcase_03 AC 57 ms
53,672 KB
testcase_04 AC 57 ms
53,680 KB
testcase_05 AC 57 ms
53,676 KB
testcase_06 AC 58 ms
51,636 KB
testcase_07 AC 82 ms
54,264 KB
testcase_08 AC 84 ms
52,196 KB
testcase_09 AC 85 ms
54,244 KB
testcase_10 AC 83 ms
53,712 KB
testcase_11 AC 83 ms
54,264 KB
testcase_12 AC 82 ms
52,196 KB
testcase_13 AC 84 ms
54,252 KB
testcase_14 AC 81 ms
52,248 KB
testcase_15 AC 79 ms
53,980 KB
testcase_16 AC 83 ms
54,256 KB
testcase_17 AC 59 ms
53,676 KB
testcase_18 AC 58 ms
53,676 KB
testcase_19 AC 58 ms
52,580 KB
testcase_20 AC 72 ms
54,244 KB
testcase_21 AC 65 ms
52,956 KB
testcase_22 AC 77 ms
54,236 KB
testcase_23 AC 79 ms
54,236 KB
testcase_24 AC 71 ms
53,680 KB
testcase_25 AC 68 ms
54,244 KB
testcase_26 AC 85 ms
54,256 KB
testcase_27 AC 61 ms
53,676 KB
testcase_28 AC 82 ms
54,264 KB
testcase_29 AC 72 ms
54,244 KB
testcase_30 AC 82 ms
54,260 KB
testcase_31 AC 61 ms
52,572 KB
testcase_32 AC 59 ms
53,672 KB
testcase_33 AC 72 ms
54,236 KB
testcase_34 AC 78 ms
53,700 KB
testcase_35 AC 84 ms
54,256 KB
testcase_36 AC 71 ms
54,248 KB
testcase_37 AC 79 ms
54,236 KB
testcase_38 AC 79 ms
54,256 KB
testcase_39 AC 81 ms
53,700 KB
testcase_40 AC 57 ms
53,672 KB
testcase_41 AC 56 ms
53,680 KB
testcase_42 AC 80 ms
54,248 KB
testcase_43 AC 83 ms
52,196 KB
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ソースコード

diff # 

import java.io.*;
import java.lang.reflect.Array;
import java.util.*;
import java.util.Map.Entry;
import java.util.function.Function;
import java.util.stream.Collectors;

@SuppressWarnings("unused")
public class Main {
	FastScanner in = new FastScanner(System.in);
	PrintWriter out = new PrintWriter(System.out);
	
	int[] num = new int[6];
	int[] pri = new int[]{500, 100, 50, 10, 5, 1};
	boolean isOk = false;
		
	//System.out.println();はつかわない！！
	void solve() throws Exception{
		int N = in.nextInt();
		if(N == 1){
			out.println("0");
			return;
		}
		
		int ans = 1;
		boolean[] isPrime = getPrime(N);
		for(int r = 3; r <= N; r++){
			if(!isPrime[r]) continue;
			long pq = (long)r * r - 2;
			if(pq > N) continue;
			if(!isPrime[(int)pq]) continue;
			ans += 2;
		}
		out.println(ans);
	}
	
	boolean[] getPrime(int n){
		boolean[] isPrime = new boolean[n+1];
		Arrays.fill(isPrime, true);
		
		if(n >= 0) isPrime[0] = false;
		if(n >= 1) isPrime[1] = false;
		
		for(int i = 2; i <= n; i++){
			if(!isPrime[i]) continue;
			for(int j = i + i; j <= n; j += i) isPrime[j] = false;
		}
		
		return isPrime;
	}
		
	public static void main(String[] args) throws Exception {
		new Main().m();
	}
	
	void m() throws Exception {
		solve();
		out.flush();
	}
	
	class FastScanner {
		Reader input;

		FastScanner() {this(System.in);}
		FastScanner(InputStream stream) {this.input = new BufferedReader(new InputStreamReader(stream));}
		
		int nextInt() {return (int) nextLong();}

		long nextLong() {
			try {
				int sign = 1;
				int b = input.read();
				while ((b < '0' || '9' < b) && b != '-' && b != '+') {
					b = input.read();
				}
				if (b == '-') {
					sign = -1;
					b = input.read();
				} else if (b == '+') {
					b = input.read();
				}
				long ret = b - '0';
				while (true) {
					b = input.read();
					if (b < '0' || '9' < b) return ret * sign;
					ret *= 10;
					ret += b - '0';
				}
			} catch (IOException e) {
				e.printStackTrace();
				return -1;
			}
		}

		double nextDouble() {
			try {
				double sign = 1;
				int b = input.read();
				while ((b < '0' || '9' < b) && b != '-' && b != '+') {
					b = input.read();
				}
				if (b == '-') {
					sign = -1;
					b = input.read();
				} else if (b == '+') {
					b = input.read();
				}
				double ret = b - '0';
				while (true) {
					b = input.read();
					if (b < '0' || '9' < b) break;
					ret *= 10;
					ret += b - '0';
				}
				if (b != '.') return sign * ret;
				double div = 1;
				b = input.read();
				while ('0' <= b && b <= '9') {
					ret *= 10;
					ret += b - '0';
					div *= 10;
					b = input.read();
				}
				return sign * ret / div;
			} catch (IOException e) {
				e.printStackTrace();
				return Double.NaN;
			}
		}

		char nextChar() {
			try {
				int b = input.read();
				while (Character.isWhitespace(b)) {
					b = input.read();
				}
				return (char) b;
			} catch (IOException e) {
				e.printStackTrace();
				return 0;
			}
		}

		String nextStr() {
			try {
				StringBuilder sb = new StringBuilder();
				int b = input.read();
				while (Character.isWhitespace(b)) {
					b = input.read();
				}
				while (b != -1 && !Character.isWhitespace(b)) {
					sb.append((char) b);
					b = input.read();
				}
				return sb.toString();
			} catch (IOException e) {
				e.printStackTrace();
				return "";
			}
		}
		
		public int[] nextIntArray(int n) {
			int[] res = new int[n];
			for (int i = 0; i < n; i++) {
				res[i] = nextInt();
			}
			return res;
		}
 
		public int[] nextIntArrayDec(int n) {
			int[] res = new int[n];
			for (int i = 0; i < n; i++) {
				res[i] = nextInt() - 1;
			}
			return res;
		}
 
		public int[] nextIntArray1Index(int n) {
			int[] res = new int[n + 1];
			for (int i = 0; i < n; i++) {
				res[i + 1] = nextInt();
			}
			return res;
		}
 
		public long[] nextLongArray(int n) {
			long[] res = new long[n];
			for (int i = 0; i < n; i++) {
				res[i] = nextLong();
			}
			return res;
		}
 
		public long[] nextLongArrayDec(int n) {
			long[] res = new long[n];
			for (int i = 0; i < n; i++) {
				res[i] = nextLong() - 1;
			}
			return res;
		}
 
		public long[] nextLongArray1Index(int n) {
			long[] res = new long[n + 1];
			for (int i = 0; i < n; i++) {
				res[i + 1] = nextLong();
			}
			return res;
		}
 
		public double[] nextDoubleArray(int n) {
			double[] res = new double[n];
			for (int i = 0; i < n; i++) {
				res[i] = nextDouble();
			}
			return res;
		}
	}
}
/* end Main */
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