Data update

Task/Farey-sequence/QBasic/farey-sequence.basic

@@ -0,0 +1,37 @@
+FUNCTION farey (n, dsc)
+    b = 1: c = 1: d = n
+
+    IF dsc = TRUE THEN a = 1: c = n - 1
+
+    cnt = cnt + 1
+    IF n < 12 THEN PRINT a; "/"; b;
+
+    WHILE ((c <= n) AND NOT dsc) OR ((a > 0) AND dsc)
+	aa = a: bb = b: cc = c: dd = d
+	k = (n + b) \ d
+	a = cc: b = dd: c = k * cc - aa: d = k * dd - bb
+	cnt = cnt + 1
+	IF n < 12 THEN PRINT a; "/"; b;
+    WEND
+
+    IF n < 12 THEN PRINT
+
+    farey = cnt
+END FUNCTION
+
+CLS
+CONST TRUE = -1: FALSE = NOT TRUE
+
+FOR i = 1 TO 9
+    PRINT USING "F# ="; i;
+    t = farey(i, FALSE)
+NEXT i
+FOR i = 10 TO 11
+    PRINT USING "F## ="; i;
+	t = farey(i, FALSE)
+NEXT i
+PRINT
+FOR i = 100 TO 900 STEP 100
+    PRINT USING "F#### = ######"; i; farey(i, FALSE)
+NEXT i
+PRINT USING "F1000 = ######"; farey(1000, FALSE)