From 7db36be20f88c8333574453ee045e8547a9956fd Mon Sep 17 00:00:00 2001 From: Shreyan Sanyal Date: Wed, 4 Oct 2023 11:25:16 +0530 Subject: [PATCH] binary search added --- Searching/binarySearch.cpp | 41 ++++++++++++++++++++++++++++++++++++++ 1 file changed, 41 insertions(+) create mode 100644 Searching/binarySearch.cpp diff --git a/Searching/binarySearch.cpp b/Searching/binarySearch.cpp new file mode 100644 index 0000000..8d9d008 --- /dev/null +++ b/Searching/binarySearch.cpp @@ -0,0 +1,41 @@ +// C++ program to implement iterative Binary Search +// Time Complexity: O(log N) +// Auxiliary Space: O(1) +#include +using namespace std; + +// An iterative binary search function. +int binarySearch(int arr[], int l, int r, int x) +{ + while (l <= r) { + int m = l + (r - l) / 2; + + // Check if x is present at mid + if (arr[m] == x) + return m; + + // If x greater, ignore left half + if (arr[m] < x) + l = m + 1; + + // If x is smaller, ignore right half + else + r = m - 1; + } + + // If we reach here, then element was not present + return -1; +} + +// Driver code +int main(void) +{ + int arr[] = { 2, 3, 4, 10, 40 }; + int x = 10; + int n = sizeof(arr) / sizeof(arr[0]); + int result = binarySearch(arr, 0, n - 1, x); + (result == -1) + ? cout << "Element is not present in array" + : cout << "Element is present at index " << result; + return 0; +}