I have been trying to learn algorithms and i have to do a basic program to find gcd of two numbers using python
so i wrote this code
def gcd_better(m, n):
i = min(m, m)
while i:
if (m % i) == 0 and (n % i) == 0:
return i
else:
i = i - 1
if __name__ == "__main__":
gcd_better(4, 20)
here I want to return i but the code is not doin that
can anyone please help me understand is there anything wrong in my code
Either print the answer in gcd or return a value, assign it to a variable in main, and print that
Since you're returning a value (i), do print(gcd_better(4, 20)) to see what is being returned.
Related
I am trying to define a function for Fibonacci series but the code is not working. I can't resolve the issues and need help to fix the problem. Whenever I am trying to call this function, last value of the series comes always greater than n, which I don't want
def fib(n):
Series = [0,1]
if n>1:
while Series[-1]<=n:
c=Series[-2]+Series[-1]
Series.append(c)
if Series[-1]>n:
break
return Series
Your code is really good, just the indentation of the return is wrong. Just align it properly.
def fib(n):
Series = [0,1]
if n>1:
while Series[-1]<=n:
c=Series[-2]+Series[-1]
Series.append(c)
return Series
do you need something like this:
def fibo(n):
l = [0,1]
for i in range(2,n+1):
l += [l[i-1] + l[i-2]]
return l
If you want to get the Fibonacci sequence up to n:
def fib(n):
series = [0,1]
if n > 1:
c = 1
while c <= n:
series.append(c)
c = series[-2] + series[-1]
return series
I am a beginner at learning python 3 and I am just writing basic programs. I wrote this simple program which would take a number in and divide it by numbers starting from 1 to the square root of the number and find the remainders and add it to a list and print it.
import math
def prime_checker(num):
n=1
list_of_remainder=[]
while n == math.floor(num**0.5):
var=int(num % n)
list_of_remainder.append(var)
n += 1
return list_of_remainder
var=prime_checker(10)
print(var)
Please tell me what I did wrong. I would like to point out here that I did try to research a bit and find error but I couldn't and only then have I posted this question.
The problem that I faced was that it printed out an empty list.
to start with, your while loop is not executed even once. The condition for your while loop is
while n == math.floor(num**0.5):
The argument num you are passing to the function prime_checker is equal to 10. In this case your condition test is:
while 1 == math.floor(10**0.5)
which is
while 1 == 3 which is obviously not true and as a result the loop is not executed even once.
import math
def prime_checker(num):
list_of_remainder = []
number=num;
n=1
x=math.floor(number**0.5)
while n <= x:
v=int(number % n)
list_of_remainder.append(v)
n += 1
return list_of_remainder
var=prime_checker(10)
print(var)
POwer in Python. How to write code to display a ^ n using funсtion?
why doesn't this code working?
a = int(input())
n = int(input())
def power(a, n):
for i in range (n):
a=1
a *= n
print(power (a, n))
Few errors:
Changing a will lose your power parameter, use result (or something else).
Move setting result = 1 outside your loop to do so once.
Multiply by a not by n.
Use return to return a value from the function
def power(a, n):
result = 1 # 1 + 2
for _ in range (n):
result *= a # 3
return result # 4
Style notes:
Setting/mutating a parameter is considered bad practice (unless explicitly needed), even if it is immutable as is here.
If you're not going to use the loop variable, you can let the reader know by using the conventional _ to indicate it (_ is a legal variable name, but it is conventional to use it when not needing the variable).
Tip: you can simple use a**n
It doesn't work because your function doesn't return the end value. Add return a to the end of the function.
ALSO:
That is not how a to the power of n is is calculated.
A proper solution:
def power(a,n):
pow_a = a
if n is 0:
return 1
for _ in range(n-1): # Substracting 1 from the input variable n
pow_a *= a # because n==2 means a*a already.
return pow_a
and if you want to be really cool, recursion is the way:
def power_recursive(a,n):
if n is 0:
return 1
elif n is 1:
return a
else:
a *= power_recursive(a,n-1)
return a
I have a task: create a function that takes a integer list as parameter and returns the sum of all even integer in an integer list, without using any kinds of loop. All addition must be done by + operator only. Below is my solution
def sumTest(list_Of_Integers):
return sum(list(filter(lambda x: x%2 == 0, list_Of_Integers)))
I want to ask if there is any better solution, like without using the built-in sum() of python.
Thanks
As stated above in the comments, a more pythonic way of doing this is to use a list comprehension:
def sumTest(list_Of_Integers):
return sum([x for x in list_Of_Integers where x % 2 == 0])
As #UloPe states, however, this sounds very much like a homework question, in which case a more recursive method may be expected (rather than using the sum() function):
def sumTest2(xs):
if len(xs) == 0:
return 0
total = xs[0] if xs[0] % 2 == 0 else 0
return total + sumTest2(xs[1:])
This will generate a function stack dependent on the size of the list.
If you want to generate a shallower stack, then you can do the following:
def sumTest3(xs):
if len(xs) == 0:
return 0
midpoint = len(xs) / 2
total = xs[midpoint] if xs[midpoint] % 2 == 0 else 0
return sumTest3(xs[:midpoint]) + total + sumTest3(xs[midpoint + 1:])
The stack depth of this version will be log(size of list)
def minimum_index(xs):
minimum_index=xs[0]
for i in range(len(xs)):
if xs[i]<xs[i+1]:
min_i=i
elif xs[i]>xs[i+1]:
min_i=i+1
continue
return minimum_index
This looks correct to me, but for some reason, I keep trying to change things around and I either get an incorrect return value or no return value.
Simplify the function
def minimum_index(xs):
ans = 0
for i in range(1, len(xs)):
if xs[i] < xs[ans]:
ans = i
return ans
or in a more pythonic way
minimum_index = lambda xs: xs.index(min(xs))
Your code has at least two issues: You seem to have two variables that stand for the minimal index, and you mix them up. Also, it is not enough to compare subsequent elements, you will have to compare to the minimal value. Try this:
def minimum_index(xs):
minx = xs[0]
mini = 0
for i in range(1,len(xs)):
if xs[i]<minx:
mini = i
minx = xs[i]
return mini
If you are using numpy, then you can simply use their numpy.argmin(xs).