github.com/captn3m0/codechef.git

---
category_name: medium
problem_code: PARALLEL
problem_name: 'Parallel Computing'
languages_supported:
    - ADA
    - ASM
    - BASH
    - BF
    - C
    - 'C99 strict'
    - CAML
    - CLOJ
    - CLPS
    - 'CPP 4.3.2'
    - 'CPP 4.9.2'
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    - D
    - ERL
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    - HASK
    - ICK
    - ICON
    - JAVA
    - JS
    - 'LISP clisp'
    - 'LISP sbcl'
    - LUA
    - NEM
    - NICE
    - NODEJS
    - 'PAS fpc'
    - 'PAS gpc'
    - PERL
    - PERL6
    - PHP
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    - 'PYTH 3.4'
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    - 'SCM qobi'
    - ST
    - TCL
    - TEXT
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max_timelimit: '1'
source_sizelimit: '50000'
problem_author: thocevar
problem_tester: laycurse
date_added: 8-12-2011
tags:
    - april12
    - medium
    - thocevar
editorial_url: 'http://discuss.codechef.com/problems/PARALLEL'
time:
    view_start_date: 1334137522
    submit_start_date: 1334137522
    visible_start_date: 1334136600
    end_date: 1735669800
    current: 1493557837
layout: problem
---
All submissions for this problem are available.Chef needs a program to solve a simple task. The program will start with an array of integers X. After the execution it should hold values X\[1\] + X\[2\] + ... + X\[i\] at all positions 1 <= i <= N. However, he wants this done fast and efficiently. He needs your help to output a program which can be executed in parallel on N machines and will produce a correct result. Note that he needs a program for some fixed size of array 1 <= N <= 1000.

A program consists of a series of synchronized steps. Instructions within one step are executed in parallel on multiple (at most N) machines which all have access to the shared memory where the array is located. You should not make any assumptions about the order in which these parallel instructions will be completed, but you can be sure that all instructions in the current step will be completed before any other instruction from the next step. There is only one type of instruction and it has the form "a+b=c". It reads the values X\[a\], X\[b\] and writes their sum in X\[c\]. The program should contain at most 20 steps and the total number of instructions should not exceed 2000.

### Input

Input contains a single positive integer N.

### Output

Output the number of steps in your program. In the following lines describe these steps. First output the number of instructions which should be executed in parallel on this step followed by a list of instructions. All items should be separated by a single space.

### Example

<pre>
<b>Input:</b>
6

<b>Output:</b>
3
2 1+2=2 4+5=5
2 2+3=3 5+6=6
3 3+4=4 3+5=5 3+6=6
</pre>### Explanation

Lets name values in the array with letters from a to f. The table below describes contents of the array after each step:

 123456initial values:abcdefafter step 1:aa+bcdd+efafter step 2:aa+ba+b+cdd+ed+e+fafter step 3:aa+ba+b+ca+b+c+da+b+c+d+ea+b+c+d+e+f