Data commit

Task/Farey-sequence/R/farey-sequence.r

@@ -0,0 +1,35 @@
+farey <- function(n, length_only = FALSE) {
+  a <- 0
+  b <- 1
+  c <- 1
+  d <- n
+  if (!length_only)
+    cat(a, "/", b, sep = "")
+  count <- 1
+  while (c <= n) {
+    count <- count + 1
+    k <- ((n + b) %/% d)
+    next_c <- k * c - a
+    next_d <- k * d - b
+    a <- c
+    b <- d
+    c <- next_c
+    d <- next_d
+    if (!length_only)
+      cat(" ", a, "/", b, sep = "")
+  }
+  if (length_only)
+    cat(count, "items")
+  cat("\n")
+}
+
+
+for (i in 1:11) {
+  cat(i, ": ", sep = "")
+  farey(i)
+}
+
+for (i in 100 * 1:10) {
+  cat(i, ": ", sep = "")
+  farey(i, length_only = TRUE)
+}