Incedo Interview questions Experienced Python Djnago

Round 1: Programming Test

1. Find four elements a, b, c and d in an array such that a+b = c+d
   

   Input:   {3, 4, 7, 1, 2, 9, 8}
   Output:  (3, 8) and (4, 7)
   Explanation: 3+8 = 4+7
   
   Input:  {65, 30, 7, 90, 1, 9, 8};
   Output:  No pairs found
   

   Solution

   def getpairs(elements):
       d=dict()
       l=len(elements)
       for i in range(l-1):
           for j in range(i+1,l):
               s=elements[i]+elements[j]
               if s not in d:
                   d[s]=(elements[i],elements[j])
               else:
                   print("pairs are %s and (%d,%d)"%(str(d[s]),elements[i],elements[j]))
   getpairs([3, 4, 7, 1, 2, 9, 8])

2. Given a number N, find the largest prime factor of that number.

   Input: 90
   Output: 5
   Input: 84
   Output: 7
   

   Solution

   def findMaxPrime(n):
       while n % 2 == 0:
           mp = 2
           n = n / 2
       for i in range(3, int(n), 2):
           while n % i == 0:
               mp = i
               n = n / i
       if n > 2:
           mp = n
       return int(mp)
   
   
   print(findMaxPrime(84))
   

3. Given two given numbers a and b where 1<=a<=b, find the number of perfect squares between a and b (a and b inclusive).

   Input: a = 9, b = 25
   Output: 3
   The three squares in given range are 9, 
   16 and 25
   

   Solution

   import math
   
   def getNumberOfSqaures(a, b):
       return (math.floor(math.sqrt(b)) - math.ceil(math.sqrt(a)) + 1)
   
   
   print("getNumberOfSqaures :", getNumberOfSqaures(9, 25))
   
   

4. Given a m x n matrix, if an element is 0, set its entire row and column to 0.

   Solution

   
   def makeZero(grid):
       row = len(grid)
       col = len(grid[0])
       r, c = list(), list()
       for i in range(row):
           for j in range(col):
               if grid[i][j] == 0:
                   r.append(i)
                   c.append(j)
       for i in range(row):
           for j in range(col):
               if i in r or j in c:
                   grid[i][j] = 0
   
   
   grid = [
       [1, 1, 1],
       [1, 0, 1],
       [1, 1, 1]
   ]
   print("input -> ", grid)
   makeZero(grid)
   print("Output -> ", grid)
   
   

Round 2: Video call interview

1. Let's have a string input = "hello world 55 test 77" then print the sum of digits of numbers in pair. output = (10,14). Don't use regular expression.

   Solution

   def getSum(string):
       """Without using regular expression"""
       k = 0
       found = False
       s = 0
       d = list()
       for i in string + " ":
           if i.strip() in [str(j) for j in range(10)]:
               s = s + int(i)
               found = True
               k = k + 1
           else:
               found = False
           if k > 0 and not found:
               d.append(s)
               s = 0
               k = 0
       print(tuple(d))
   
   getSum("hello world 55 test 77")
   

2. How to give time out error when a process takes more than the expected time ? Raise the error and kill the process

   Solution

   import time
   import multiprocessing
   
   def raise_time_out():
       p = multiprocessing.Process(target=testtime, args=[10])
       p.start()
       p.join(5)
       if p.is_alive():
           print('Process taking more than 5 seconds..Lets kill it')
           p.terminate()
           p.join()
   
   if __name__ == "__main__":
       start = time.perf_counter()
       raise_time_out()
       end = time.perf_counter()
       print(f'Processing finished in {end - start} seconds')
   

3. What are the python libraries you have used ? Answer - math, requests, re, random, bs4, numpy, pandas etc..
4. What are the technologies you are using in your current project ? Answer - Python, Django, Oracle Data base, GiT etc..
5. How will you design an app to get the lowest fare for a bus ticket. The design should have details about source, destination, lowest fare. Give the details and code for Model, View and Templates used in Django.
6. Parent and Base classes in python ?
7. What is yield in python ?
8. What does tail command do in UNIX ?