DSA/interpolation_iter.py

51 lines
1.1 KiB
Python

# Python program to implement interpolation search
# using iteration approach
def interpolationSearch(arr, n, x):
# Find indexes of two corners
low = 0
high = (n - 1)
# Since array is sorted, an element present
# in array must be in range defined by corner
while low <= high and x >= arr[low] and x <= arr[high]:
if low == high:
if arr[low] == x:
return low;
return -1;
# Probing the position with keeping
# uniform distribution in mind.
pos = int(low + (((float(high - low)/( arr[high] - arr[low])) * (x - arr[low]))))
# Condition of target found
if arr[pos] == x:
return pos
# If x is larger, x is in upper part
if arr[pos] < x:
low = pos + 1;
# If x is smaller, x is in lower part
else:
high = pos - 1;
return -1
# Main function
if __name__ == "__main__":
# Array of items on whighch search will
# be conducted.
arr = [10, 12, 13, 16, 18, 19, 20, 21,
22, 23, 24, 33, 35, 42, 47]
n = len(arr)
x = 18 # Element to be searched
index = interpolationSearch(arr, n, x)
# If element was found
if index != -1:
print ("Element found at index",index)
else:
print ("Element not found")