Modified

Author: Rezwan

HackerRank/DefaultDict Tutorial.py

@@ -0,0 +1,14 @@
+'''
+Created on Jun 9, 2016
+
+@author: Md. Rezwanul Haque
+'''
+from collections import defaultdict
+
+d, n = defaultdict(list), list(map(int, input().split()))
+
+for i in range(n[0]):
+    d[input()].append(i + 1)
+
+for i in range(n[1]):
+    print(' '.join(map(str, d[input()])) or -1)

HackerRank/Tuples.py

@@ -0,0 +1,7 @@
+'''
+Created on May 5, 2016
+@author: Md. Rezwanul Haque
+'''
+input()
+ans  = hash(tuple(map(int,input().split())))
+print(ans)

Tuples and Dictionaries.py

@@ -0,0 +1,223 @@
+####### Tuples #########
+
+'''
+* A tuple is a sequence of immutable Python objects. Tuples are sequences, just like lists.
+'''
+
+# Define a tuple
+my_tuple = ()
+
+my_tuple = (1,2,3,5,4)
+print(my_tuple) # (1, 2, 3, 5, 4)
+
+
+my_tuple = ('Hello', 1, "World", 7)
+print(my_tuple) # ('Hello', 1, 'World', 7)
+print(my_tuple[0]) # Hello
+print(my_tuple[3]) # 7
+print(my_tuple[1:3]) # (1, 'World')
+
+
+# Tuples usually supports the sequence operations supported by string and lists:
+
+# Concatenation
+a = (1, 3)
+b = (2, 4)
+c = a + b
+print(c) # (1, 3, 2, 4)
+
+# Repetition
+a = (1,2,3,4,5)
+b = 2
+c = a * b
+print(c) #  (1, 2, 3, 4, 5, 1, 2, 3, 4, 5)
+
+# Indexing and slicing
+a = (1, 2, 3, 4, 5)
+print(a[0], a[1:5]) # 1 (2, 3, 4, 5)
+
+# List to tuple
+my_list = [1, 2,3, 4, 5]
+my_tuple = tuple(my_list)
+print(my_tuple) # (1, 2, 3, 4, 5)
+
+
+# Sort a tuple
+my_tuple = (2, 5, 1, 4, 3)
+a = sorted(my_tuple) # It converts tuple to list and sort
+print(a) # [1, 2, 3, 4, 5]
+
+
+######
+B = (1, [2, 3], 4)
+B[1][0] = 'spam'
+print(B) # (1, ['spam', 3], 4)
+
+# how to add value to a tuple?
+t = (1,2,3)
+t = t + (1,)
+print (t) # (1,2,3,1)
+
+a = (1,2,3,5,6)
+a = a[:3] + (4,) + a[3:]
+print(a) # (1, 2, 3, 4, 5, 6)
+
+# How to input an integer tuple from user?
+my_tuple = tuple(map(int,input().split()))
+print(my_tuple)
+
+###
+my_tuple = ()
+for i in range(5):
+    a = int(input())
+    my_tuple += (a,)
+
+print(my_tuple)
+'''
+Input:
+1
+2
+3
+4
+5
+
+Output:
+(1, 2, 3, 4, 5)
+'''
+
+
+
+
+
+############### Dictionaries ###################
+# empty dictionary
+my_dict = {}
+
+# dictionary with integer keys
+my_dict = {1: 'apple', 2: 'ball'}
+print(my_dict) # {1: 'apple', 2: 'ball'}
+
+# dictionary with mixed keys
+my_dict = {'name': 'John', 1: [2, 4, 3]}
+print(my_dict) # {'name': 'John', 1: [2, 4, 3]}
+
+# using dict()
+my_dict = dict({1:'apple', 2:'ball'})
+print(my_dict)  # {1: 'apple', 2: 'ball'}
+
+# from sequence having each item as a pair
+my_dict = dict([(1,'apple'), (2,'ball')])
+print(my_dict) # {1: 'apple', 2: 'ball'}
+
+
+
+### How to access elements from a dictionary?
+my_dict = {1: 'Rezwan', 'Haque' : 7}
+print(my_dict[1]) # Rezwan
+print(my_dict['Haque']) # 7
+print(my_dict.get('Haque')) # 7
+print(my_dict.keys()) # dict_keys([1, 'Haque'])
+
+
+
+### Python Dictionary methods (https://www.programiz.com/python-programming/dictionary)
+'''
+clear()	=> Remove all items form the dictionary.
+
+copy()	=> Return a shallow copy of the dictionary.
+
+fromkeys(seq[, v]) => Return a new dictionary with keys from seq and value equal to v (defaults to None).
+
+get(key[,d]) =>	Return the value of key. If key doesnot exit, return d (defaults to None).
+
+items()	=> Return a new view of the dictionary's items (key, value).
+
+keys()	Return a new view of the dictionary's keys.
+
+pop(key[,d]) => Remove the item with key and return its value or d if key is not found. If d is not provided and key is not found, raises KeyError.
+
+popitem() => Remove and return an arbitary item (key, value). Raises KeyError if the dictionary is empty.
+
+setdefault(key[,d]) =>	If key is in the dictionary, return its value. If not, insert key with a value of d and return d (defaults to None).
+
+update([other])	=> Update the dictionary with the key/value pairs from other, overwriting existing keys.
+
+values() => Return a new view of the dictionary's values
+
+'''
+
+
+# Map two lists into a dictionary in Python
+keys = ['a', 'b', 'c']
+values = [1, 2, 3]
+my_dict = dict(zip(keys, values))
+print(my_dict) # {'a': 1, 'b': 2, 'c': 3}
+
+## OR
+my_dict = dict((k, v) for k, v in zip(keys, values))
+print(my_dict) # {'a': 1, 'b': 2, 'c': 3}
+
+
+d = {'a0': [1, 2, 3], 'a1': [4, 5, 6]}
+my_dict = zip(*d.values())
+print(*my_dict) # (1, 4) (2, 5) (3, 6)
+
+
+x = ['1', '2', '3', '4']
+y = [[1,0],[2,0],[3,0],[4,]]
+my_dict = {key:value for key, value in zip(x,y)}
+print(my_dict) # {'1': [1, 0], '2': [2, 0], '3': [3, 0], '4': [4]}
+
+
+### Make a dictionary in Python from input values
+strs="""A1023 CRT
+        A1029 Regulator
+        A1030 Therm"""
+
+my_dict = dict(x.split() for x in strs.splitlines())
+print(my_dict) # {'A1023': 'CRT', 'A1029': 'Regulator', 'A1030': 'Therm'}
+
+
+
+#####
+n = int(input())          #n is the number of items you want to enter
+d ={}
+for i in range(n):
+    text = input().split()     #split the input text based on space & store in the list 'text'
+    d[text[0]] = text[1]       #assign the 1st item to key and 2nd item to value of the dictionary
+print(d)
+'''
+Input:
+3
+A1023 CRT
+A1029 Regulator
+A1030 Therm
+
+Output: 
+{'A1023': 'CRT', 'A1029': 'Regulator', 'A1030': 'Therm'}
+'''
+
+
+
+'''Important Link: 
+(1) Add new keys to a dictionary? (https://stackoverflow.com/questions/1024847/add-new-keys-to-a-dictionary)
+(2) Map two lists into a dictionary in Python (https://stackoverflow.com/questions/209840/map-two-lists-into-a-dictionary-in-python)
+(3) zip two values from the dictionary in Python (https://stackoverflow.com/questions/32222563/zip-two-values-from-the-dictionary-in-python)
+(4) Python equivalent of zip for dictionaries (https://stackoverflow.com/questions/16458340/python-equivalent-of-zip-for-dictionaries)
+(5) Make a dictionary in Python from input values (https://stackoverflow.com/questions/14147369/make-a-dictionary-in-python-from-input-values)
+
+'''
+
+
+
+
+
+'''
+** You are now able to solve following online-judge problems.
+_____________________________________________________________
+(1) HackerRank | DefaultDict Tutorial
+(2) HackerRank | Tuples
+
+'''
+
+