TheAlgorithms-C-Plus-Plus/search/interpolation_search2.cpp
2020-05-29 23:26:30 +00:00

50 lines
1.4 KiB
C++

/**
* \file
* \brief [Interpolation
* search](https://en.wikipedia.org/wiki/Interpolation_search) algorithm
*/
#include <iostream>
/** function to search the value in an array using interpolation search
* \param [in] arr array to search in
* \param [in] value value to search for
* \param [in] len length of array
* \returns index where the value is found
* \returns -1 if not found
*/
int InterpolationSearch(int A[], int n, int x)
{
int low = 0;
int high = n - 1;
while (low <= high)
{
int mid = low + (((high - 1) * (x - A[low])) / (A[high] - A[low]));
if (x == A[mid])
return mid; // Found x, return (exit)
else if (x < A[mid])
high = mid - 1; // X lies before mid
else
low = mid + 1; // x lies after mid
}
return -1;
}
/** main function */
int main()
{
int A[] = {2, 4, 5, 7, 13, 14, 15, 23};
int x = 17;
///< passed array A inside the InterpolationSearch function
int index = InterpolationSearch(A, 8, x);
if (index < 0)
std::cout << "Number " << x << " not found" << std::endl;
else
std::cout << "Number " << x << " is at " << index << std::endl;
}
// randomly set x bcoz array was defined by us , therefore not reasonable for
// asking input. We could have asked for input if array elements were inputed by
// the user.