rot cipher

Tags: Mathematics Cipher Time limit:1000 ms Memory limit:10000 K Total submissions:19502 Accepted:5239 DescriptionBob and Alice started to use a brand-new encoding scheme. surprisingly it is not a public key cryptosystem, but their encoding and decoding is based on secret keys. they chose the secret key at their last meeting in Philadelphia on February 16th, 1996. they chose as a secret key a sequence of N disti

1031: [JSOI2007] character encryption cipher time limit:10 Sec Memory limit:162 MBsubmit:7248 solved:3138[Submit] [Status] [Discuss] Description like to delve into the problem of JS classmate, and recently fascinated by the encryption method of thinking. One day, he suddenly came up with what he thought was the ultimate encryption: to make a circle of information that needs to be encrypted, it is clear that they have many different ways of re

[JSOI2007] Character encryption cipher time limit:10 Sec Memory limit:162 MBsubmit:7859 solved:3410[Submit] [Status] [Discuss] Description like to delve into the problem of JS classmate, and recently fascinated by the encryption method of thinking. One day, he suddenly came up with what he thought was the ultimate encryption: to make a circle of information that needs to be encrypted, it is clear that they have many different ways of reading.

Same plaintext same algorithm get different cipher principle:Every time the user login plaintext is the same, the password has not changed for the user, but the password is not the same every time, mainly because of the time stamp (month and day), the server will generate two passwords : 1. Password for the current time 2. One-minute password in advanceFor example: User 11:23 login------> server will generate two passwords:11:2311:22 A password is cor

In order to improve the transmission speed of SCP, the SCP encryption algorithm is specified as Arcfour $ scp-c arcfour localfile Username@remoteip:remotefile get error Unknown cipher type $ ssh-c Username@remoteip Get an error no matching cipher found Workaround: Find/etc/ssh/sshd_config, and add a line to the end of the file Ciphers 3DES-CBC,BLOWFISH-CBC,CAST128-CBC,ARCFOUR,ARCFOUR128,ARCFOUR256,AES

Title Description A password machine generates a password as follows: First enter a series of numbers into the machine, then take out some of them, and then get a new number as the password. Now please simulate the operation of such a machine, the user through the input Control command to generate the password. A sequence is stored in the cipher machine and is initially empty. There are 3 types of control commands for the

Public Static voidMain (string[] args) {Try{String plaintext= "Duwenlei"; Keypairgenerator Keypairgenerator= Keypairgenerator.getinstance ("RSA"); Keypairgenerator.initialize (2048); KeyPair KeyPair=Keypairgenerator.generatekeypair (); //SignatureMessageDigest MD = messagedigest.getinstance ("SHA1"); byte[] Enchash =md.digest (Plaintext.getbytes ()); Pkcs8encodedkeyspec KeySpec=NewPkcs8encodedkeyspec (Keypair.getprivate (). getencoded ()); Keyfactory keyfactory= Keyfactory.getinstance ("RSA"); K

DescriptionLike to delve into the problem of JS classmate, and recently fascinated by the encryption method of thinking. One day, he suddenly came up with what he thought was the ultimate encryption: to make a circle of information that needs to be encrypted, it is clear that they have many different ways of reading. For example, it can be read as:JSOI07 soi07j oi07js i07jso 07JSOI 7jsoi0 sort them by the size of the string: 07JSOI 7jsoi0 i07jso JSOI07 oi07js soi07j read the last column of chara

evaluated array, and N is Len intI, j, k =0; for(i =1; I i; for(i =0; I k) { for(K. k--:0, j = Sa[ranking[i]-1]; R[i + K] = = R[j + K]; k++); }}intSA[MAXN], R[MAXN];strings;intSTR[MAXN];intMain () {//freopen ("1031.in", "R", stdin); //freopen ("1031.out", "w", stdout); //Cin.sync_with_stdio (false);CIN >>s; intn =s.length (); S= S +s; for(inti =0; I 2; Str[s.length ()]=1; Da (str, SA, s.length ()+1, the); for(inti =0; I ) { if(sa[i]>=n)Continue; intp = Sa[i] + N-1; coutS[p]; } cou

A hash is the conversion of the target text into an irreversible hash string (or message digest) of the same length, whereas encryption (Encrypt) converts the target text into a reversible cipher with different lengths. This article mainly introduces PHP commonly used hash encryption function, in the case of a detailed analysis of PHP hash encryption function usage, code with detailed comments, easy to understand, the need for friends can refer to, Th

toN-1 DoInc (Wc[wd[i]); $ fori:=1 toM Dowc[i]:=wc[i-1]+Wc[i]; - fori:=n-1 Downto 0 Do - begin the Dec (wc[wd[i]]); -sa[wc[wd[i]]]:=Y[i];Wuyi End; the - fori:=0 toN Doswap (x[i],y[i]); Wu -p:=1; x[sa[0]]:=0; About fori:=1 toN-1 Do $ begin - ifCMP (sa[i-1],SA[I],J) Thenx[sa[i]]:=p-1 - Else beginX[sa[i]]:=p; Inc (P);End; - End; A +j:=j*2; them:=p; - End; $ End; the the the begin theAssign (input,'bzoj1031r.in'); Reset (input); -Assign (output,'Bzoj1031r

Because we're going to be poor here. The password includes 0-9,a-z,a-z a total of 62 characters, so we use 62 binary to traverse.First, we implement a 10 binary to 62 binary method. private static char[] CharSet = "0123456789abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ". ToCharArray (); private static string[] CharSet = {"0", "1", "2", "3", "4", "5", "6", "7", "8", "9",// "A", "B", "C", "D", "E", "F",

Description like to delve into the problem of JS classmate, and recently fascinated by the encryption method of thinking. One day, he suddenly came up with what he thought was the ultimate encryption: to make a circle of information that needs to be encrypted, it is clear that they have many different ways of reading. For example, it can be read as:JSOI07 soi07j oi07js i07jso 07JSOI 7jsoi0 sort them by the size of the string: 07JSOI 7jsoi0 i07jso JSOI07 oi07js soi07j read the last column of char

Mathematical. X^2% n = 1 (x+1) (x-1) = kn. Set x+1 = K1*n1, x-1=k2*n2. Then K1*k2=k, N1*n2=n. It is possible to calculate the approximate number of each greater than sqrt (n) and then make the N1,N2 attempt separately. Calculate x Be sure to take the mold. Otherwise 1 will become n+1. #include #include#include#include#includeusing namespacestd;Const intMAXN =100000+Ten;intRES[MAXN];intn,m,cnt;Long Longt,j;intMain () {CIN>> N; Cnt=0; if(n==1) {printf ("none\n");return 0;} M=(int) sqrt (n+0.5); f

Topic: Given a two-dimensional matrix, the sub-matrix of the a*b with the most occurrences is obtained.Two-dimensional hash, just remember that the vertical base can not be the same, love how to engage in how to doThe natural overflow result from the beginning of writing OLE thought it was a natural overflow was stuck out and then wrote a double modulo ... The result is still OLEFinally found that the problem read into the pit dad ... There are spaces in the string not to say, full of invisible

Test Instructions:LinkMethod:Permutation groupparsing:Quite a simple permutation group? But the first time was too two to think wrong. I thought I was going to just follow that sequence and get the power of the permutation group OK. The results found that I did not affect this many loops-it is not funny. So hurry back and ask for a loop. For each of the intra-cycle permutations, the water problem is followed.Code:#include #include #include #include #define Nusing namespace STD;intN,k;intA[n];int

#include #include #include #include using namespace Std;int main (){int ce[26], co[26];string encrypted, orginal;String::size_type I, Len;Ios::sync_with_stdio (FALSE);while (CIN >> encrypted >> orginal){memset (CE, 0, sizeof (CE));memset (Co, 0, sizeof (CO));Len = Orginal.length ();for (i = 0; i {++ce[encrypted[i]-' A '];++co[orginal[i]-' A '];}Sort (CE, ce+26);Sort (Co, co+26);if (Equal (CE, ce+26, CO))cout Elsecout }return 0;}UVa1339 Ancient Cipher

The program task is to convert the genetic phonetic alphabet to 6 digits, we can use any well-remembered pinyin string, the transformation process is as follows, the first step, the string six a group of folding up, such as wangximing into: WangxiMingIn the second step, we want to add the ASCII value of all the characters perpendicular to the same position, and draw out 6 numbers, as the example above, then draw 228 202 206Then the number of each digit processing, that is, the number of each bit

Cipher Time limit:1000 ms Memory limit:10000 K Total submissions:19228 Accepted:5148 DescriptionBob and Alice started to use a brand-new encoding scheme. surprisingly it is not a public key cryptosystem, but their encoding and decoding is based on secret keys. they chose the secret key at their last meeting in Philadelphia on February 16th, 1996. they chose as a secret key a sequence of N distinct integers, A1 ;.

Poj 1026 Cipher (replacement group) Link: poj 1026 Given n integers (1-n) as keys, a string is given, Evaluate the k-encoded string Analysis: brute-force solving times out and can be solved using the knowledge of the replacement group. Replacement group: a one-to-one transformation of a finite set is called replacement. A pair of replicas form a replacement group. For a set a (a [1], a [2], a [3]... a [n ]), (B [a [1], B [a [2], B [a [3]... B [a [n])