Update interpolation_search.c

1) Easy logic built
2) error minimized: as array is increasing in above example it might not always be increasing.just replace 47 by 2 then run above program it will give an incorrect ans. but in improvised case it is minimized.
3)we are scanning input from user so, more saturated
4)'position' is more reliable than 'index'.

Searches/interpolation_search.c

@@ -1,24 +1,12 @@
-
+#include<stdio.h>
 int interpolationSearch(int arr[], int n, int x)
-{
-    int lo = 0, hi = (n - 1);
- 
-    while (lo <= hi && x >= arr[lo] && x <= arr[hi])
+{ 
+    int q=NULL;
+    while(q<n)
     {
-       
-        int pos = lo + (((double)(hi-lo) /
-              (arr[hi]-arr[lo]))*(x - arr[lo]));
- 
-       
-        if (arr[pos] == x)
-            return pos;
- 
-        
-        if (arr[pos] < x)
-            lo = pos + 1;
- 
-        else
-            hi = pos - 1;
+     if(arr[q]==x)
+     return q;
+     q++;
     }
     return -1;
 }
@@ -28,16 +16,19 @@ int main()
 {
     // Array of items on which search will
     // be conducted.
+    int x;
     int arr[] =  {10, 12, 13, 16, 18, 19, 20, 21, 22, 23,
                   24, 33, 35, 42, 47};
     int n = sizeof(arr)/sizeof(arr[0]); //To get length of an array
- 
-    int x = 18; // Element to be searched
+    
+    printf("Enter the no, to be searched");
+    scanf("%d",&x); // Element to be searched
+    
     int index = interpolationSearch(arr, n, x);
  
     // If element was found
     if (index != -1)
-        printf("Element found at index %d", index);
+        printf("Element found at position %d", index+1);
     else
         printf("Element not found.");
     return 0;