Student needs some help please!!

[fonz87]

I got some programs that i need help with and it would be awesome if someone can help me out with them. I've been lurking around this site and hopefully someone can help me. Thank you

I m writing a program that should take number n and output it's sum of it.
for example if i enter 5 it should output 55
1^2+2^2+3^2+4^2+5^2=55
for far i m getting nothing.. a error of 15.. its adding up the numbers but not ^2 them.

def times(y):
    sum=0
    for i in range(1,y+1):

        sum+=i
    return sum
def main():
    x=input("Enter a number")
    w=times(x)
    print w
main()

Problem 2

this program is asking for numbers into words.. so far i got this

import string

def letters(l):
    a=str(l)
   
def main():
    x=raw_input("Enter some numbers to be written out")
    mylist=[]
    sentinel="*"
    while (x!=sentinel):
        y=eval(x)
        mylist.append(y)
        x=raw_input("Enter some numbers to be written out")       
    z=letters(mylist) 
    print z
main()

but in the program letters.. i was going to put in the if statements like this ..

if x==10:
            print "ten"
        if x==9:
            numnine=x
            print "nine"
        if x==8:
            numeight=x
            print "eight"
        if x==7:
            numseven=x
            print "seven"
        if x==6:
            numsix=x
            print "six"

but the thing is .. it has to go up to 999 i can write out all the numbers which will take me a whole day but there is got to be a shorter way of doing it

problem 3

i got to write this program in a recursively way.. where when i enter numbers in a list it should print out the reverse list in a exact way not using built in fuction.. i got it to work using reverse fuction but thats built in ..and i got it to print reverse but its sorting it..

here is the sorting way

import string
def reverse(L):
    m=len(L)
    for i in range(m-2):
        for j in range(m-1):
            if L[j]<L[j+1]:
                L[j],L[j+1]=L[j+1],L[j]
          
def main():
    x=raw_input("Enter numbers to reverse it")
    mylist=[]
    sentinel="*"
    while (x!=sentinel):
        y=eval(x)
        mylist.append(y)
        x=raw_input("Enter numbers to reverse it")   
    w=reverse(mylist)
    print w
main()

well it was sorting but now its print none

lastly

how do i get started with a program to write the A-Z and returns its permutations ..
for example.. write ab.. it prints ab, ba, if i enter abc it print abc bca cab acb n etc

if anyone can help me with this.. .that would be awesome... thank you!!!

[sneekula]

On problem #1 you want the sum of squares:

def times(y):
    sum = 0
    for i in range(1, y+1):
        # you want the sum of squares
        sum += i * i
    return sum

def main():
    x = input("Enter a number: ")
    w = times(x)
    print w

main()

This looks a lot like C, a bit more pythonic would be:

# sum of squares of a sequence 1 ... n
# if n is 5 then the sum is 1^2 + 2^2 + 3^3 + 4^4 + 5^5

n = 5

print sum([i*i for i in range(1, n+1)])  # 55

[fonz87]

Man it's always little things that i always miss.. thanks .. i knew i had to do something with multiply i. thanks

I still need help with others.

[fonz87]

Hey guys i figured out a way to do the problems.. i got little help from a friend.. i just need help with the problem number 2.. if someone can help me with that. .that would be awesome.! thanks again for all ur help people

[gwarguy]

Im very new at python, but as for the converting numbers to letters, im pretty sure you can make a list or whatever is the equivalent to an array in python, to solve the issue of having to type 0-999 out. would just be x = [0:1000] because it stops before the last number

[jrcagle]

Here's a start:

digits = {0:"zero, 1:"one", 2:"two", etc.}

print digits[2]

HTH,
Jeff