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### SyrianCheatersHunter's blog

By SyrianCheatersHunter, 9 months ago, ,

# MNM algo

Once upon a time, three Syrian competitive programmers decided to spend their time in doing research and studies. they worked hard. Finally, hard work paid off and they discovered the algorithm -which Codeforces uses to catch cheaters [the ones who violate Codeforces contest rules]. Their lives have just become easier and now they can copy codes from each other / Ideone without spending time changing variables names and methods declarations order.

Those three inventors are Math_Master, NourAlhadi, Mr.spring. (hats off people ...).

MNM -(first letters of Math_Master, NourAlhadi, Mr.spring respectively)- Cheating Algorithm is -in my opinion, the greatest since the invention of breadth/depth-first search algorithms.

## MNM is simple, here is a simple explanation for it:

• MNM relies on "divide and conquer" approach in solving div2 contest- problems. Problems are divided amongst Math_Master, NourAlhadi, Mr.spring.
• MNM uses multithreading among M-N-M brains to solve the problems and urges those M-N-M to share the solutions in a Facebook chat, so all three participants submit their solutions with a simple addition.

• Submit the new codes immediately and avoid cheat detection.

#### Latest achievement:

Problem A Math_Master 35623761 NourAlhadi 35622851 same code with header2. Mr.spring 35623758 same code.

Problem B All failed with the same solution,

Problem D CheatersHunter is bored from writing but you got the Idea.

 #include <bits/stdc++.h>
#define PB push_back
#define MP make_pair
#define X first
#define Y second
#define SCD(a) scanf("%d",&a)
#define SCD2(a,b) scanf("%d %d",&a,&b)
#define SCLL(a) scanf("%lld",&a)
#define SCLL2(a,b) scanf("%lld %lld",&a,&b)
#define PRD(a) printf("%d\n",a)
#define PRLL(a) printf("%lld\n",a)
#define speed ios_base::sync_with_stdio(0); cin.tie(0); cout.tie(0)
#define sz(v) ((int)v.size())
#define all(v) v.begin(),v.end()
#define endl "\n"
#define MEMO memset(memo,-1,sizeof memo)
#define SP setprecision
#define hafo GodessOfHope
#define TEST int test; cin>>test; for (int Test=1;Test<=test;Test++)
using namespace std;

void files (bool in,char *s){ if (in) freopen(s,"r",stdin); else freopen(s,"w",stdout);}
const double PI = 4 * atan(1.0);
const double EPS = 1e-9;
const int infi = (int)1e9;
const long long infl = (long long)1e17;
const int MOD = (int) 1e9+7;
const int MAX = (int) 1e6+22;
const int dx[] = {0,1,-1,0,0,1,1,-1,-1};
const int dy[] = {0,0,0,-1,1,1,-1,1,-1};
const int kdx[] ={1,1,-1,-1,2,2,-2,-2};
const int kdy[] ={2,-2,2,-2,1,-1,1,-1};


 #include <bits/stdc++.h>
#define PB push_back
#define MP make_pair
#define X first
#define Y second
#define SCD(a) scanf("%d",&a)
#define SCD2(a,b) scanf("%d %d",&a,&b)
#define SCLL(a) scanf("%lld",&a)
#define SCLL2(a,b) scanf("%lld %lld",&a,&b)
#define PRD(a) printf("%d\n",a)
#define PRLL(a) printf("%lld\n",a)
#define speed ios_base::sync_with_stdio(0); cin.tie(0); cout.tie(0)
#define sz(v) ((int)v.size())
#define all(v) v.begin(),v.end()
#define endl "\n"
#define MEMO memset(memo,-1,sizeof memo)
#define SP setprecision
#define hafo GodessOfHope
#define TEST int test; cin>>test; for (int Test=1;Test<=test;Test++)
using namespace std;

void files (bool in,char *s){ if (in) freopen(s,"r",stdin); else freopen(s,"w",stdout);}
const double PI = 4 * atan(1.0);
const double EPS = 1e-9;
const int infi = (int)1e9;
const long long infl = (long long)1e17;
const int MOD = (int) 1e9+7;
const int MAX = (int) 1e6+22;
const int dx[] = {0,1,-1,0,0,1,1,-1,-1};
const int dy[] = {0,0,0,-1,1,1,-1,1,-1};
const int kdx[] ={1,1,-1,-1,2,2,-2,-2};
const int kdy[] ={2,-2,2,-2,1,-1,1,-1};

typedef long long ll;
typedef unsigned long long ull;
typedef long double ld;
typedef vector <int> vi;
typedef vector <ll> vll;
typedef vector <vi> vvi;
typedef vector <vll> vvll;
typedef pair<int,int> pii;
typedef pair<ll,ll> pll;
typedef vector<pii> vpii;
typedef vector<pll> vpll;


# WorldsNobelPrize in creativity goes to Math_Master,NourAlhadi,Mr.spring

•
• +322
•

 » 9 months ago, # |   +39 Wow, constant time complexity guys,Way to go ...
•  » » 9 months ago, # ^ |   +33 I think we will need Math_Master to provide a mathematical proof.
•  » » » 9 months ago, # ^ |   +32 Math_Master is busy with something else:35629979 ll fuck[123]; ll sex[123]; ll xvideos[123]; ll xxnx[123]; 
•  » » » » 9 months ago, # ^ |   +16 dear johnnySins,YOU GOT A RIVAL HERE.
 » 9 months ago, # |   +29
•  » » 9 months ago, # ^ |   +24 )
•  » » » 9 months ago, # ^ |   +19 Maf Master is in the house.
 » 9 months ago, # |   +30 They thought it's an ACM competition :D
 » 9 months ago, # |   +141 Thank you. I'll handle it.
•  » » 9 months ago, # ^ |   -9 congrats [user:Math_Master][user:NourAlhadi][user:Mr.spring] as you are going to receive the cure for a dangerous disease!
•  » » 9 months ago, # ^ | ← Rev. 3 →   -18 Sir mike , two cheat detected , Rafiqul01 and mahade31 used approximately same code of 467 Div2 B problem in contest time.Their submissions are : 35705915 and 35703893 , they just changed the variables names . I think cheater is Rafiqul01 because he submitted later than mahade31 . They two got accepted and they two got rating updated , but why ? I think plagiarism check should be more efficient .
•  » » 9 months ago, # ^ |   -6 This is one of the reasons I love the community..ReportImproveRepeat
 » 9 months ago, # |   -79 world's -> worlds prize -> prise yeah ,it's the new English <3 gay(Guy according to The New English) you should take some courses in English before writing any blog.
•  » » 9 months ago, # ^ |   +67 There is a lot of anger and hatred in your comment, I recommend you to get help ASAP.FYI it's 2018 and being gay is okay. bullies like you -living in the stone age- can no longer annoy others.Excuse me for my English.I am not a native speaker -(Obviously). However, it seems you got the idea of my blog. looking forward to writing about you in my next blogs.#NoCheaterIsSafeFromSCH
•  » » » 9 months ago, # ^ |   -59 خريا مستر مبعوص !! سائل عنك ولا عن بلوغاتط لانو هههههههه
•  » » » » 9 months ago, # ^ |   -55 كل هاد انبعصت لان الشباب جابو الـE وما اخدوا منك
•  » » » 9 months ago, # ^ |   -49 واذا ماعرفتني فانا شخص ...سبق واعترفتلي بجحشنتك ^_^
 » 9 months ago, # |   +11 Such amazing research should be rewarded wit a huge rating increase like 2^31
•  » » 9 months ago, # ^ |   +12 Too bad codeforces stores rating with an int (maybe idk) so their ratings will overflow into negative :(
 » 9 months ago, # | ← Rev. 6 →   0 Are you CheaterKiller?
•  » » 9 months ago, # ^ | ← Rev. 2 →   +11 Nope, I am new to this job.It seems I will start my own startup and welcome programmers from all over the world to catch those cheaters in codeforces.#NoCheaterIsSafeFromSyrianCheatersHunter
•  » » 8 months ago, # ^ |   0 LOL. I've retired :P Actually, I just realized it's waste of time and I had a great rating increase (of course in main account :D) after this. For your information, this amount of increase is like ~800. Please don't try to find my main account :P.And one thing, we can't prevent all cheaters in the contest, there will be always a cheat in a contest, so work for yourself and kill them by placing better than them instead of reporting.(As you can see I also improved my English :P)
 » 9 months ago, # |   0 They thought it is a virtual contest . :D
 » 9 months ago, # |   +40 Can we add a new color to CF (half red half blue) for police?