From 3fc70f1ccd93da57b2d4c101a13db1d8b1001002 Mon Sep 17 00:00:00 2001
From: Arpita23r <arpita2302r@gmail.com>
Date: Thu, 9 Oct 2025 20:12:03 +0530
Subject: [PATCH 1/2] added ternary search

---
 searches/ternary.search.R | 27 +++++++++++++++++++++++++++
 1 file changed, 27 insertions(+)
 create mode 100644 searches/ternary.search.R

diff --git a/searches/ternary.search.R b/searches/ternary.search.R
new file mode 100644
index 00000000..827cfdf5
--- /dev/null
+++ b/searches/ternary.search.R
@@ -0,0 +1,27 @@
+# Ternary Search in R – works on sorted arrays
+
+ternary_search <- function(arr, target) {
+  l <- 1
+  r <- length(arr)
+  while (r >= l) {
+    mid1 <- l + (r - l) %/% 3
+    mid2 <- r - (r - l) %/% 3
+    if (arr[mid1] == target) return(mid1)
+    if (arr[mid2] == target) return(mid2)
+    if (target < arr[mid1]) r <- mid1 - 1
+    else if (target > arr[mid2]) l <- mid2 + 1
+    else {
+      l <- mid1 + 1
+      r <- mid2 - 1
+    }
+  }
+  return(-1)
+}
+
+arr <- as.integer(strsplit(readline("Enter sorted integers: "), " ")[[1]])
+target <- as.integer(readline("Enter target to search: "))
+index <- ternary_search(arr, target)
+if (index != -1)
+  cat("Element found at position:", index, "\n")
+else
+  cat("Element not found.\n")
\ No newline at end of file

From 55e254ddff50312fd11df114f4053009aa290a03 Mon Sep 17 00:00:00 2001
From: Arpita Roy <100989922+Arpita23r@users.noreply.github.com>
Date: Sat, 11 Oct 2025 14:42:59 +0530
Subject: [PATCH 2/2] Update ternary.search.R

---
 searches/ternary.search.R | 40 ++++++++++++++++++++++++++++++++-------
 1 file changed, 33 insertions(+), 7 deletions(-)

diff --git a/searches/ternary.search.R b/searches/ternary.search.R
index 827cfdf5..0c2e16a0 100644
--- a/searches/ternary.search.R
+++ b/searches/ternary.search.R
@@ -1,16 +1,26 @@
+#' Performs ternary search on a sorted integer array.
+#'
+#' @param arr Integer vector. Must be sorted in ascending order.
+#' @param target Integer value to search for in arr.
+#' @return The index (1-based) of the target in arr if found, otherwise -1.
+#' @details The input array must be sorted in ascending order for correct results.
 # Ternary Search in R – works on sorted arrays
 
 ternary_search <- function(arr, target) {
   l <- 1
   r <- length(arr)
-  while (r >= l) {
+  while (l <= r) {
     mid1 <- l + (r - l) %/% 3
     mid2 <- r - (r - l) %/% 3
+
     if (arr[mid1] == target) return(mid1)
     if (arr[mid2] == target) return(mid2)
-    if (target < arr[mid1]) r <- mid1 - 1
-    else if (target > arr[mid2]) l <- mid2 + 1
-    else {
+
+    if (target < arr[mid1]) {
+      r <- mid1 - 1
+    } else if (target > arr[mid2]) {
+      l <- mid2 + 1
+    } else {
       l <- mid1 + 1
       r <- mid2 - 1
     }
@@ -18,10 +28,26 @@ ternary_search <- function(arr, target) {
   return(-1)
 }
 
-arr <- as.integer(strsplit(readline("Enter sorted integers: "), " ")[[1]])
-target <- as.integer(readline("Enter target to search: "))
+# --- User Input Section with Validation ---
+arr_input <- readline("Enter sorted integers: ")
+arr_split <- strsplit(arr_input, " ")[[1]]
+arr <- as.integer(arr_split)
+if (length(arr) == 0 || any(is.na(arr))) {
+  cat("Error: Please enter a non-empty list of valid integers separated by spaces.\n")
+  quit(status = 1)
+}
+
+target_input <- readline("Enter target to search: ")
+target <- suppressWarnings(as.integer(target_input))
+if (is.na(target_input) || is.na(target)) {
+  cat("Error: Please enter a valid integer for the target.\n")
+  quit(status = 1)
+}
+
+# --- Execute Search ---
 index <- ternary_search(arr, target)
+
 if (index != -1)
   cat("Element found at position:", index, "\n")
 else
-  cat("Element not found.\n")
\ No newline at end of file
+  cat("Element not found.\n")