AP2 - AP - Complete The Series (Easy)

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Arithmatic and geometric Progressions are 2 of the well known progressions in maths.

Arithmatic progression(AP) is a set in which the difference between 2 numbers in constant. for e.g., 1, 3, 5, 7, 9 .... In this series the difference between 2 numbers is 2.

The task here is very simple indeed.

You will be given the 3rd term , 3rd last term and the sum of the series. You need print length of the series & the series.


First line will contain a number indicating the number of test cases.

Each of the following t lines will have 3 number '3term' ,'3Lastterm' and 'sum'

3termĀ  - is the 3rd term in of the series and

3LasttermĀ  - is the 3rd term in of the series and

sum - is the sum of the series.


For each input of the test case, you need to print 2 lines.

First line should have 1 value - the number of terms in the series.

2nd line of the output should print the series numbers separated by single space.


3 8 55

1 2 3 4 5 6 7 8 9 10


  • In all the test cases, all the series elements are positive integers.
  • The series will have at least 7 elements.
  • number of test cases <=100.
  • All the numbers will fit in 64 bits (long long in C)

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adarshtadwai: 2018-10-18 13:26:28

1st term + last term = 2nd term + last 2nd term = 3rd term + last 3rd term
this observation is helpful and directly gives n

harshjalan_99: 2018-09-29 18:25:18

Last edit: 2018-09-29 18:26:28
Yauhen: 2018-09-21 15:39:09

It's misconception here in statements that n >=7. I'm pretty sure it's >= 6.

nitishyadav169: 2018-08-16 19:30:42

What is this
Same solution
first Give TLE
and At last Accepted

kranthi_0003: 2018-08-11 14:39:57

easy ...AC in one go:)

Last edit: 2018-08-11 14:40:14
candyzack: 2018-08-06 13:36:04

Last edit: 2018-08-06 13:36:55
yaswanth desu: 2018-03-29 05:56:06

guys, don't go to quadratic. try to solve it in linear equation itself.

Try to remember that sn = n/2*(first term + last term) ..(you can actually and simply derive).
And also don't take 3rd and last3rd as some variable and start the problem.It will complicate you. take starting element as some variable.Then get other elements from it.

Simple basic maths related to Arithmatic progression , which we learned in child.

vivek_dwivedi: 2018-03-25 18:37:09

my first problem in SPOJ Ac in one go ;)

aman786: 2018-01-28 19:15:57

Yooooo AC in two GO ;)

ducky94tb: 2018-01-14 13:15:50

which fast i/o should use to be accepted in java?

Added by:Devil D
Time limit:0.100s
Source limit:1500B
Memory limit:1536MB
Cluster: Cube (Intel G860)
Languages:All except: ASM64