#include <bits/stdc++.h>
using namespace std;

void interpolationSearch(int *a, int n, int data)
{
    int low = 0, k, high = n - 1;
    while (low <= high)
    {
        k = low + (((data - a[low]) * (high - low)) / (a[high] - a[low]));
        if (data == a[k])
        {
            cout << "data found" << endl;
            return;
        }
        if (data < a[k])
            high = k - 1;
        else
            low = k + 1;
    }
    cout << "data not found" << endl;

    return;
}

int main()
{

    int n, data;

    // enter array length
    cout << "enter size of data\n";
    cin >> n;

    int *a = (int *)(malloc(sizeof(int) * n));

    // fill the array
    cout << "enter data\n";
    for (int i = 0; i < n; i++)
        scanf("%d", &a[i]);

    cout << "enter element to be searched" << endl;
    cin >> data;

    interpolationSearch(a, n, data);

    return 0;
}

Output

enter size of data
5
enter data
10
12
14
16
17
enter element to be searched
14
data found