From 280ddcd6f0e157f89947bd4bd942f5854e6767c7 Mon Sep 17 00:00:00 2001
From: Shardendu Kumar <72930487+shardendu930@users.noreply.github.com>
Date: Sat, 15 Oct 2022 22:32:43 +0530
Subject: [PATCH] Create Interpolationsearch.cpp

Added interpolation search
---
 C++/Interpolationsearch.cpp | 61 +++++++++++++++++++++++++++++++++++++
 1 file changed, 61 insertions(+)
 create mode 100644 C++/Interpolationsearch.cpp

diff --git a/C++/Interpolationsearch.cpp b/C++/Interpolationsearch.cpp
new file mode 100644
index 0000000..ba062a4
--- /dev/null
+++ b/C++/Interpolationsearch.cpp
@@ -0,0 +1,61 @@
+// C++ program to implement interpolation
+// search with recursion
+#include <bits/stdc++.h>
+using namespace std;
+
+// If x is present in arr[0..n-1], then returns
+// index of it, else returns -1.
+int interpolationSearch(int arr[], int lo, int hi, int x)
+{
+	int pos;
+
+	// Since array is sorted, an element present
+	// in array must be in range defined by corner
+	if (lo <= hi && x >= arr[lo] && x <= arr[hi]) {
+
+		// Probing the position with keeping
+		// uniform distribution in mind.
+		pos = lo
+			+ (((double)(hi - lo) / (arr[hi] - arr[lo]))
+				* (x - arr[lo]));
+
+		// Condition of target found
+		if (arr[pos] == x)
+			return pos;
+
+		// If x is larger, x is in right sub array
+		if (arr[pos] < x)
+			return interpolationSearch(arr, pos + 1, hi, x);
+
+		// If x is smaller, x is in left sub array
+		if (arr[pos] > x)
+			return interpolationSearch(arr, lo, pos - 1, x);
+	}
+	return -1;
+}
+
+// Driver Code
+int main()
+{
+
+	// Array of items on which search will
+	// be conducted.
+	int arr[] = { 10, 12, 13, 16, 18, 19, 20, 21,
+				22, 23, 24, 33, 35, 42, 47 };
+
+	int n = sizeof(arr) / sizeof(arr[0]);
+
+	// Element to be searched
+	int x = 18;
+	int index = interpolationSearch(arr, 0, n - 1, x);
+
+	// If element was found
+	if (index != -1)
+		cout << "Element found at index " << index;
+	else
+		cout << "Element not found.";
+
+	return 0;
+}
+
+// This code is contributed by equbalzeeshan