Create life.rexx

life.rexx

@@ -0,0 +1,81 @@
+/* Conway's Game of Life in REXX  */
+
+rows = 20
+cols = 40
+generations = 12
+
+/* Initialize world with random data */
+do row = 1 to rows
+    do col = 1 to cols
+        world.row.col = random(0, 1)
+    end
+end
+
+/* Display the initial world */
+say 'Initial World:'
+call DisplayWorld
+
+/* Run through generations */
+do gen = 1 to generations
+    say 'Generation:' gen
+    call NextGeneration
+    call DisplayWorld
+end
+exit
+
+NextGeneration:
+    /* Temporary world for calculations */
+    do row = 1 to rows
+        do col = 1 to cols
+            neighbors = CountNeighbors(row, col)
+            /* Apply rules of the Game */
+            if world.row.col = 1 then do
+                if neighbors < 2 | neighbors > 3 then
+                    temp.row.col = 0
+                else
+                    temp.row.col = 1
+            end
+            else do
+                if neighbors = 3 then
+                    temp.row.col = 1
+                else
+                    temp.row.col = 0
+            end
+        end
+    end
+
+    /* Copy the temp world to the main world */
+    do row = 1 to rows
+        do col = 1 to cols
+            world.row.col = temp.row.col
+        end
+    end
+    return
+
+CountNeighbors:
+    parse arg row, col
+    neighbors = 0
+    do dr = -1 to 1
+        do dc = -1 to 1
+            if dr = 0 & dc = 0 then iterate
+            nr = row + dr
+            nc = col + dc
+            if nr > 0 & nr <= rows & nc > 0 & nc <= cols then
+                neighbors = neighbors + world.nr.nc
+        end
+    end
+    return neighbors
+
+DisplayWorld:
+    do row = 1 to rows
+        line = ''
+        do col = 1 to cols
+            if world.row.col = 1 then
+                line = line || '#'
+            else
+                line = line || ' '
+        end
+        say line
+    end
+    return
+