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In Python, how can I make it so the first 2 elements of a list are added together, then the first 4, then the first 6, and so on? [closed]

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I am making a game where two players take turns adding a number 1 to 10 to the running total. The player who adds to get 100 wins. I stored the inputs of the players in a list, and at the end of the game, I want to display the total after every turn. The list is in the format:
allTurns = [player1move1, player2move1, player1move2, player2move2, ...]
How can I add only the first 2 elements and display them, then add only the first 4 elements and display them, and then the first 6, and so on?

for i in range(0, len(list)):
if i % 2 == 0:
print(sum(list[:i+1]))
Or
sums = []
for i in range(0, len(list)):
if i % 2 == 0:
sums.append(sums[-1] + list[i-1] + list[i])

Try this:
allTurns = [1,2,3,6,12,23]
out = []
for n in range(len(allTurns)):
if n % 2 is 1:
out.append(allTurns[n] + allTurns[n-1])
if len(allTurns) % 2 is 1:
out.append(allTurns[-1])
print(out)
I've coded it so that it could work for any situation, and not just yours.

Try this:
allTurns = [1,2,3,6,12,23,4]
out = []
for n in allTurns:
if allTurns.index(n) % 2 is 0:
i = 0
for a in range(allTurns.index(n)+2):
try:
i=i+allTurns[a]
except IndexError:
pass
out.append(i)
print(out)
This is probably as simple as it can get.

Extract n first consecutive numbers from a string in python [closed]

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Let's consider this string :
st = 'text1text6253text'
How could I please extract the two first consecutive figures ?
Expected output :
62

You can either use regex with \d{2}and return that, or go over the string:
st = 'text1text6253text'
for i in range(len(st)-1):
if st[i].isdigit() and st[i+1].isdigit():
print(st[i]+st[i+1])
break

import re
def find_con(n, s):
result = re.search('\d{%s}'%n, s)
return result.group(0) if result else result
st = 'text1text6253text'
print(find_con(2, st))

st = 'text1text6253text'
lst = list(st)
lst2 = []
for i,v in enumerate(lst):
if lst[i].isdigit() and lst[i+1].isdigit():
lst2.append(lst[i])
lst2.append(lst[i+1])
ans = int(lst2[0] + lst2[1])
print(ans)

Thanks to your answers, I built a general function that I propose you below :
def extract_n_consecutive_numbers(st,nb):
for i in range(len(st)-nb+1):
is_numeric = True
for j in range(nb):
is_numeric = is_numeric & st[i+j].isdigit()
if is_numeric :
output = ""
for j in range(nb):
output += st[i+j]
return output
return ""
Example :
extract_n_consecutive_numbers('text1text6253text',2)
Out[1]: 62

python not understanding simple math question [closed]

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I am making mortgage calculator, I have provided information for variables p, i, n, but get error in the equation.
p[i(1 + i) ^ n] / [(1 + i) ^ n – 1]

What you shared is not valid python code. Here is an example of code that will accomplish what you are asking:
# define function:
def CalculateMortgage(p, i, n):
# calculate numerator:
numerator = p * (i *(1+i) ** n)
# calculate denominator:
denominator = ((1+i) ** n - 1)
# calculate mortgage:
mortgage = numerator/denominator
# return result:
return mortgage
# set variables:
p = 1
i = 1
n = 1
# call function:
mortgage = CalculateMortgage(p, i, n)
# print result:
print('Your mortgage is: ' + str(mortgage))

Project Euler 55 - Answer Only Off By 3 (strange!) [closed]

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I was solving this problem (found at http://projecteuler.net/problem=55) and I could not get it right so I searched for the answer.
It seems the answer my code is giving is only off by 3 (mine: 246 , right: 249).
It would be nice for someone to to spot the mistake. I have been trying for 3 hours now...
Here is my code:
from time import time
def rev(x):
return int(str(x)[::-1])
def Palindrome(x):
if x == rev(x): return True
else : return False
def test(x):
steps = 0
while True :
if not Palindrome(x):
steps += 1
else:
return False
if steps > 50 :
return True
x += rev(x)
def main():
starttime = time()
lychrel = 0
for i in range(1,10000):
if test(i) : lychrel += 1
elapsed = time() - starttime
print "The answer is %d found in %f seconds" %(lychrel,elapsed)
if __name__ == "__main__":
main()
Thanks in advance!

From the description at http://projecteuler.net/problem=55
Surprisingly, there are palindromic numbers that are themselves Lychrel numbers; the first example is 4994.
Your code does not recognize 4994 as a Lychrel number.

is there possible to resolve this star pyramid [closed]

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Today, i have trying to resolve a small star pyramid :
Input:
5 1
Output:
*
**
***
****
Code:
x = 1
y = 0
m, e = map(int, raw_input().split())
while x < m:
print "\n" * y, "*" * e
m -= 1
e += 1
I did that but there is a better solution?? Thanks =)

I think this can be solved more easily:
stop, first = map(int, raw_input().split())
for i in range(stop - 1):
print '*' * (i + first)

just for fun >:)
class c:
def __init__(s,m,e):
s.e , s.m = sorted([e, m])
s.r = 42
def __iter__(s):
return s
def next(s):
if s.m < s.e:
t = "".join(chr(s.r) for _ in range(s.m))
s.m += 1
return t
else:
raise StopIteration
print "\n".join(c(*map(int,raw_input().split())))

n = int(raw_input())
for i in range(n): print "*"*i
This appears to do what your program intends to do, however I can't quite tell because of the issues I raised in my comment above.