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Diffstat (limited to 'OLD/csci1913/Java/lab5_strap012.java')
-rw-r--r-- | OLD/csci1913/Java/lab5_strap012.java | 90 |
1 files changed, 0 insertions, 90 deletions
diff --git a/OLD/csci1913/Java/lab5_strap012.java b/OLD/csci1913/Java/lab5_strap012.java deleted file mode 100644 index 45a101b..0000000 --- a/OLD/csci1913/Java/lab5_strap012.java +++ /dev/null @@ -1,90 +0,0 @@ -// -// SIEVE. The Sieve of Eratosthenes. -// -// James B. Moen -// 08 Oct 19 -// -// Test the SIEVE class, for 30 points total. -// - -// -// Put your code for the class SIEVE here!!! -// -class Sieve { - private boolean[] numbers; - private int realMax; - public Sieve(int max){ - if (max<2) - throw new IllegalArgumentException(); - numbers = new boolean[max]; - realMax = (max - 1); - for (int i=2; i<max; i+=1) { numbers[i]=true; } - } - public void findPrimes() { - for (int i=2; i<=realMax; i+=1) { - //Only look for composite numbers if the number is prime - if (numbers[i]) { - for (int j=(i*2); j<=realMax; j+=i) { - numbers[j]=false; - } - } - // System.out.println(i); - } - } - public String toString(){ - String str = ""; - for (int n = 0; n <= realMax; n += 1) { - if (numbers[n]) { - str += n; str += " "; - } - } - return str; - } -} -// TOSS THE KNEES. Run SIEVE on some examples. - -class TossTheKnees -{ - -// MAIN. Find some primes. - - public static void main(String [] args) - { - Sieve sieve = null; // We must initialize SIEVE or Java will cry. - -// 5 points. This must print "Sieve size must be at least 2." but without the -// quotes. - - try - { - sieve = new Sieve(0); - } - catch (IllegalArgumentException oops) - { - System.out.println("Sieve size must be at least 2."); - } - -// 5 points. This must print nothing. - - try - { - sieve = new Sieve(100); - } - catch (IllegalArgumentException oops) - { - System.out.println("Sieve size must be at least 2."); - } - -// 10 points. This must print integers from 2 to 99, separated by blanks. - - System.out.println(sieve); - -// 10 points. This must print the prime numbers between 2 and 99, separated by -// blanks. They are: -// -// 2 3 5 7 11 13 17 19 23 29 31 37 41 43 47 53 59 61 67 71 73 79 83 89 97 - - sieve.findPrimes(); - System.out.println(sieve); - } -} |