Please write a program which count and print the numbers of each character in a string input by console.
Example: If the following string is given as input to the program:
abcdefgabc
Then, the output of the program should be:
a,2
c,2
b,2
e,1
d,1
g,1
f,1
Use dict to store key/value pairs. Use dict.get() method to lookup a key with default value.
Main author's Solution: Python 2
dic = {}
s=raw_input()
for s in s:
dic[s] = dic.get(s,0)+1
print '\n'.join(['%s,%s' % (k, v) for k, v in dic.items()])My Solution: Python 3
import string
s = input()
for letter in string.ascii_lowercase:
cnt = s.count(letter)
if cnt > 0:
print("{},{}".format(letter,cnt))OR
s = input()
for letter in range(ord('a'),ord('z')+1): # ord() gets the ascii value of a char
letter = chr(letter) # chr() gets the char of an ascii value
cnt = s.count(letter)
if cnt > 0:
print("{},{}".format(letter,cnt))'''Solution by: Utkarsh4697
'''
s = 'abcdefgabc'
for i in sorted(set(s)):
print(f'{i}, {s.count(i)}')'''Solution by: popomaticbubble
'''
def character_counter(text):
characters_list = list(text)
char_count = {}
for x in characters_list:
if x in char_count.keys():
char_count[x] += 1
else:
char_count[x] = 1
return char_count
def dict_viewer(dictionary):
for x, y in dictionary.items():
print(f"{x},{y}")
text = input("> ")
dict_viewer(character_counter(text))Please write a program which accepts a string from console and print it in reverse order.
Example: If the following string is given as input to the program:*
rise to vote sir
Then, the output of the program should be:
ris etov ot esir
Use list[::-1] to iterate a list in a reverse order.
Main author's Solution: Python 2
s=raw_input()
s = s[::-1]
print sMy Solution: Python 3
s = input()
s = ''.join(reversed(s))
print(s)Please write a program which accepts a string from console and print the characters that have even indexes.
Example: If the following string is given as input to the program:
H1e2l3l4o5w6o7r8l9d
Then, the output of the program should be:
Helloworld
Use list[::2] to iterate a list by step 2.
Main author's Solution: Python 2
s=raw_input()
s = s[::2]
print sMy Solution: Python 3
s = "H1e2l3l4o5w6o7r8l9d"
s = [ s[i] for i in range(len(s)) if i%2 ==0 ]
print(''.join(s))OR
s = "H1e2l3l4o5w6o7r8l9d"
ns =''
for i in range(len(s)):
if i % 2 == 0:
ns+=s[i]
print(ns)Please write a program which prints all permutations of [1,2,3]
Use itertools.permutations() to get permutations of list.
Solution:
import itertools
print list(itertools.permutations([1,2,3]))"""Solution by: popomaticbubble
"""
from itertools import permutations
def permuation_generator(iterable):
p = permutations(iterable)
for i in p:
print(i)
x = [1,2,3]
permuation_generator(x)Write a program to solve a classic ancient Chinese puzzle: We count 35 heads and 94 legs among the chickens and rabbits in a farm. How many rabbits and how many chickens do we have?
Use for loop to iterate all possible solutions.
Solution:
def solve(numheads,numlegs):
ns='No solutions!'
for i in range(numheads+1):
j=numheads-i
if 2*i+4*j==numlegs:
return i,j
return ns,ns
numheads = 35
numlegs = 94
solutions=solve(numheads,numlegs)
print solutions"""Solution by: popomaticbubble
"""
import itertools
def animal_counter(lst):
chickens = 0
rabbits = 0
for i in lst:
if i == 2:
chickens += 1
elif i == 4:
rabbits += 1
print(f"Number of chickens is {chickens}\nNumber of rabbits is {rabbits}")
def animal_calculator(total_legs, total_heads, legs_of_each_species):
combinations = itertools.combinations_with_replacement(legs_of_each_species, total_heads)
correct_combos = []
for i in list(combinations):
if sum(i) == total_legs:
correct_combos.append(i)
print(correct_combos)
for i in correct_combos:
animal_counter(i)
animal_calculator(94, 35, legs_of_each_species=[2,4])