tasks a-s

Task/Run-length-encoding/PowerBASIC/run-length-encoding.powerbasic

@@ -0,0 +1,52 @@
+FUNCTION RLDecode (i AS STRING) AS STRING
+    DIM Loop0 AS LONG, rCount AS STRING, outP AS STRING, m AS STRING
+
+    FOR Loop0 = 1 TO LEN(i)
+        m = MID$(i, Loop0, 1)
+        SELECT CASE m
+            CASE "0" TO "9"
+                rCount = rCount & m
+            CASE ELSE
+                IF LEN(rCount) THEN
+                    outP = outP & STRING$(VAL(rCount), m)
+                    rCount=""
+                ELSE
+                    outP = outP & m
+                END IF
+        END SELECT
+    NEXT
+    FUNCTION = outP
+END FUNCTION
+
+FUNCTION RLEncode (i AS STRING) AS STRING
+    DIM tmp1 AS STRING, tmp2 AS STRING, outP AS STRING
+    DIM Loop0 AS LONG, rCount AS LONG
+
+    tmp1 = MID$(i, 1, 1)
+    tmp2 = tmp1
+    rCount = 1
+
+    FOR Loop0 = 2 TO LEN(i)
+        tmp1 = MID$(i, Loop0, 1)
+        IF tmp1 <> tmp2 THEN
+            outP = outP & TRIM$(STR$(rCount)) & tmp2
+            tmp2 = tmp1
+            rCount = 1
+        ELSE
+            INCR rCount
+        END IF
+    NEXT
+
+    outP = outP & TRIM$(STR$(rCount))
+    outP = outP & tmp2
+    FUNCTION = outP
+END FUNCTION
+
+FUNCTION PBMAIN () AS LONG
+    DIM initial AS STRING, encoded AS STRING, decoded AS STRING
+    initial = INPUTBOX$("Type something.")
+    encoded = RLEncode(initial)
+    decoded = RLDecode(encoded)
+    'in PB/Win, "?" = MSGBOX; in PB/DOS & PB/CC. "?" = PRINT
+    ? initial & $CRLF & encoded & $CRLF & decoded
+END FUNCTION