// Array of items

static int arr[] = new int[] { 10, 11, 13, 17, 18, 19, 20, 21, 22, 23, 27, 32, 35, 41, 45 };

// If x is present in arr[0..n-1], then it will return index of it, else -1.

static int interpolationSearch(int x) {

// Find indexes of two corners

int lo = 0, hi = (arr.length - 1);

// Since array is sorted, an element present

// in array must be in range defined by corner

while (lo <= hi && x >= arr[lo] && x <= arr[hi]) {

if (lo == hi) {

if (arr[lo] == x)

return lo;

return -1;

}

// Probing the position with keeping

// uniform distribution in mind.

int pos = lo + (((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 upper part

if (arr[pos] < x)

lo = pos + 1;

// If x is smaller, x is in the lower part

else

hi = pos - 1;

}

return -1;

}

// Driver method

public static void main(String[] args) {

int x = 18; // Element to be searched

int index = interpolationSearch(x);

// If element was found

if (index != -1)

System.out.println("Element found at index " + index);

else

System.out.println("Element not found.");

}

}