dfgshsjghfdsjkl.txt

来自「java经典程序源代码」· 文本 代码 · 共 73 行

public class Sieve 
{ 
private static boolean[] sieve(int range) 
{ 
boolean[] isPrime = new boolean[range + 1]; 
for (int i = 1; i < isPrime.length; i++) 
{ 
isPrime[i] = true; 
} 

isPrime[1] = false; 

int n = (int) Math.ceil(Math.sqrt(range)); 
for (int j = 1; j <= n; j++) 
{ 
if (isPrime[j]) 
{ 
for (int k = 2 * j; k <= range; k += j) 
{ 
isPrime[k] = false; 
} 
} 
} 

return isPrime; 
} 

private static int findLargest(boolean[] isPrime) 
{ 
int largest = isPrime.length - 1; 
for (; !isPrime[largest]; largest--); 

return largest; 
} 

public static void main(String[] args) 
{ 
BufferedReader input = new BufferedReader(new InputStreamReader( 
System.in)); 
int param = 0; 

try 
{ 
param = Integer.parseInt(input.readLine()); 
} 
catch (NumberFormatException e) 
{ 
System.out.println("Invalid Argument."); 
} 
catch (IOException e) 
{ 
e.printStackTrace(); 
} 

boolean[] isPrime = sieve(param); 
for (int i = 1; i < isPrime.length; i++) 
{ 
System.out.print(isPrime[i] + ", "); 
} 

System.out.println(); 
System.out.println(findLargest(isPrime)); 
} 
} 



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if (isExist("Wolf comes.")) 
{ 
me.doRunAway(topSpeed); 
}