Finish lab (rather easy)

1 files changed, 29 insertions, 4 deletions

diff --git a/csci1913/Java/lab5_strap012.java b/csci1913/Java/lab5_strap012.java
index f7f9467..45a101b 100644
--- a/csci1913/Java/lab5_strap012.java
+++ b/csci1913/Java/lab5_strap012.java
@@ -10,10 +10,35 @@
 //
 //  Put your code for the class SIEVE here!!!
 //
-class sieve {
-  
-  public sieve(){
-    for 
+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.