Created Sieve of Eratosthenes (markdown)

2024-11-22 12:34:23 +00:00 · 2017-11-27 19:47:25 -05:00 · 2017-11-27 19:47:25 -05:00 · 9efaf6516b
commit 9efaf6516b
parent 8ed96582b3
1 changed files with 45 additions and 0 deletions
--- a/Sieve-of-Eratosthenes.md
+++ b/Sieve-of-Eratosthenes.md
@ -0,0 +1,45 @@
+Here is the well-known Sieve of Eratosthenes algorithm for finding prime numbers, written in EightBall:
+
+    ' Sieve of Eratosthenes                                                         
+                                                                                
+    ' Globals                                                                       
+    byte nr = 10                                                                    
+    word n = nr * nr                                                                
+    byte A[n] = 1                                                                   
+                                                                                
+    pr.msg "Sieve of Eratosthenes ..."; pr.nl                                       
+    call doall()                                                                    
+    end                                                                             
+                                                                                
+    sub doall()                                                                     
+      call sieve()                                                                  
+      call printresults()                                                           
+    return 0                                                                        
+                                                                                
+    sub sieve()                                                                     
+      word i = 0; word j = 0                                                        
+      for i = 2 : (nr - 1)                                                          
+        if A[i]                                                                     
+          j = i * i                                                                 
+          while (j < n)                                                             
+            A[j] = 0                                                                
+            j = j + i                                                               
+          endwhile                                                                  
+        endif                                                                       
+      endfor                                                                        
+    return 0                                                                        
+                                                                                
+    sub printresults()                                                              
+      word i = 0                                                                    
+      for i = 2 : (n - 1)                                                           
+      if A[i]                                                                     
+        if i > 2                                                                  
+          pr.msg ", "                                                             
+        endif                                                                     
+        pr.dec i                                                                  
+      endif                                                                       
+    endfor                                                                        
+    pr.msg "."                                                                    
+  return 0                                                                        
+                                                                                
+