if the first caracter has a number less than 5 you should think on cyclic form.
Exemple: the first carater given is d..the numro of 'd' is 3 and 3-5<0...so you have to add 26 and of course d comes y(because 3-5+26=24 and y has 24)...
i whish i am clarified the point...good luck

Does anyone knows what is tested in the test 6??? Or anyone have examples????

Edited by author 09.05.2010 11:37

please give some test

#include <stdio.h>
int main()
{
    int string[200];
    int len=0;
    char ch;
    int count;
    ch=getchar();
    while(!((ch=='\0')||(ch=='EOF')||(ch=='\n')))
    {
        string[len]=ch-'a';
        len++;
        ch=getchar();
    }
    string[len]='\0';
    //perviy prohod
    if(len==1)
    {
        printf("%c\0",string[0]-5);
        return 0;
    }
    if (string[0]<5)
        string[0]+=26;
    for(count=1;count<len;count++)
    {
        while(string[count]<string[count-1])
            string[count]=string[count]+26;
    }
    //vtoroy prohod
    for(count=len-1;count>0;count--)
    {
        string[count]=string[count]-string[count-1];
    }
    string[0]=string[0]-5;
    //tretiy prohod
    for(count=0;count<len;count++)
    {
        printf("%c",string[count]+'a');
    }
    printf("\0");
    return 0;
}

#include <iostream>
using namespace std;

int main(void)
{
    char encry[101];
    int temp[101];
    char dencry[101];

    memset(encry, 0, 101*sizeof(char));
    memset(temp, 0, 101*sizeof(int));
    memset(dencry, 0, 101 * sizeof(char));

    fgets(encry, 101, stdin);

    for (int i=0; i<strlen(encry)-1; i++)
    {
        temp[i] = encry[i] - 'a';
    }

    if (temp[0] < 5)
    {
        temp[0] += 26;
    }

    for (int i=1; i<strlen(encry)-1; i++)
    {
        while (temp[i] < temp[i-1])
        {
            temp[i] += 26;
        }
    }

    for (int i=strlen(encry)-1; i>0; i--)
    {
        temp[i] = temp[i] - temp[i-1];
        dencry[i] = temp[i] + 'a';
    }

    temp[0] -= 5;
    dencry[0] += temp[0] + 'a';

    for (int i=0; i<strlen(encry)-1; i++)
    {
        cout << dencry[i];
    }
    cout << endl;
    return 0;
}

#include <iostream.h>
int main()
{const int n=100;
char a[101];
int i,b[n];
for(i=0;i<n;i++) cin>>a[i];
for(i=0;i<n;i++) b[i]=a[i]-'a';
if(b[0]<=5) b[0]=b[0]+26;
for(i=1;i<=n;i++) while(a[i]<a[i-1]) b[i]=b[i]+26;
for(i=1;i<=n;i++) b[i]=b[i]-b[i-1];
b[0]=b[0]-5;
for(i=0;i<n;i++) a[i]=(b[i]+'a');
for(i=0;i<n;i++) cout<<a[i]<<endl; return 0;}

var s:string;
    s1:array [1..100] of char;
    a,b:array [1..100] of integer;
    i,j,n:integer;
begin
  readln(s);
  n:=length(s);
  for i:=1 to n do
    a[i]:=ord(s[i])-97;
  for i:=n downto 2 do         {24+x-26 = 17}
    begin
      b[i]:=(a[i]+26-a[i-1])mod 26;
      s1[i]:=chr(b[i]+97);
    end;
  s1[1]:=chr(((a[1]-5)mod 26)+97);
  for i:=1 to n do
    write(s1[i]);
  readln;
end.
WA on 4th test!!!

It`s my Pascal code:
type mass=array[1..101] of shortint;
var i,j,j1:integer; s:string[101]; m1:mass;
begin
read(s); j1:=length(s);
for i:=1 to j1 do
begin
m1[i]:=ord(s[i])-97;
end; j:=5;
for i:=1 to j1 do
begin
if m1[i]>=j-1 then begin m1[i]:=m1[i]-j; j:=m1[i]+j; end
else begin m1[i]:=m1[i]+26-j; j:=m1[i]-26+j end
end;
for i:=1 to j1 do write(chr(m1[i]+97)); end.

Give me some tests were my program will give wrong answer..

#include <iostream.h>
#include <stdio.h>

using namespace std;

int main()
{
  char * s;
  cin >> s;

  int a[200] = {5};
  for (int i = 0; i < strlen(s); i++)
    a[i+1] = (s[i] - 'a');
  int n = strlen(s);

  for (int i = n; i >= 1; i--)
  {
     a[i] -= a[i-1];
     if (a[i] < 0) a[i] += 26;
  }

  for (int i = 1; i <= n; i++)
    cout << (char)(a[i]+'a');

}

why compilation error!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

#include <iostream.h>
#include <string.h>
void main()
{char a[102];
int b[100],i,n;
for (i=0;i<n;i++)
cin>>a;
for(i=0;i<n;i++)
{ b[i]= int(a[i]- 'a');
if(i==0){if(b[i]<5)
b[i]+=26;
cout<<char(b[i]-5+'a');}}
else  {if(b[i]<b[i-1]) b[i]+=26;
coun<<char(b[i]-b[i-1]+'a');}}
i don't understed where is my mistake

Edited by author 03.09.2008 18:05

How can we get word "secret" from "xbduyr"?
This is mistake!!
Please, can you write the same table of this transformation?

This is very foolish task. I think, it hasn't right answer.
It is not really to describe all sides of this program!!!

#include<stdio.h>
#include<math.h>
#include<string.h>
#include<stdlib.h>

int i,u,n,minus,v[128],aux,auxs;
char st[128],auxx;

int main()
{
    #ifndef ONLINE_JUDGE
    freopen("1404.in","r",stdin);
    freopen("1404.out","w",stdout);
    #endif
    scanf("%s",st);
    u=strlen(st);
    for(i=0;i<u;i++)
        v[i]=(int)(st[i])-'a';
    for(i=0;i<u;i++)
    {
        if(i==0)
            v[i]+=26;
        else
            while(v[i]<v[i-1])
                v[i]+=26;
    }
    minus=5;
    for(i=0;i<u;i++)
    {
        auxs=st[i]-st[i]+(v[i]-minus)%26+'a';
        printf("%c",auxs);
        minus=v[i];
    }
    return 0;
}

Also what here it is wrong??? You see only latin letters!!
using System;
    class Program
    {
        static void Main(string[] args)
        {
            string s = Console.ReadLine();

            if (s != null)
            {
               int[] s1 = new int[s.Length];
                int[] s3 = new int[s.Length];
                string s2 = "abcdefghijklmnopqrstuvwxyz";
                int tmp = 26;
                for (int i = 0; i < s.Length; i++)
                {
                    if (i == 0)
                    {
                        s1[i] = s2.IndexOf(s[i]);
                        if (s1[i] <= 4)
                        {
                            s1[i] += 26;
                        }
                    }
                    else
                    {
                        s1[i] = s2.IndexOf(s[i]);
                        while (s1[i] < s1[i - 1])
                        {
                            s1[i] += tmp;
                        }
                    }
                }
                tmp = s1[1];
                int tmp1;
                s1[1] -= s1[0];
                for (int i = 2; i < s1.Length; i++)
                {
                    tmp1 = s1[i];
                    s1[i] -= tmp;
                    tmp = tmp1;
                }

                s = "";
                s1[0] -= 5;
                for (int i = 0; i < s1.Length; i++)
                {
                    s += s2[s1[i]];
                }
                           }
           Console.WriteLine(s);

        }
    }

Edited by author 24.04.2007 18:31

This is my code.
{program Ryan;
var
 n,i,k:integer;
 a:array[0..1000] of char;
 b:array[0..25] of 'a'..'z';
 c,d:array[0..1000] of integer;
begin
 for i:=0 to 25 do
 b[i]:=chr(i+97);
 i:=-1;
 repeat
  i:=i+1;
  read(a[i]);
  c[i]:=ord(a[i])-97;
  if (c[i]<26)and(i<>0)
  then while (c[i]<c[i-1])or (c[i]<26) do
       c[i]:=c[i]+26;
 until eoln;
 d[0]:=c[0]-5;
 for n:=0 to i do
 if n<>0
 then d[n]:=c[n]-c[n-1];
 for n:=0 to i do
 if d[n]>26
 then begin d:=c;   break;  end;
 while k<i+1 do
 begin
 write(b[d[k]]);
 k:=k+1;
 end;
end.}
And I have sth. didn't understand.
That is if I input 'asdffg',what is the output?
Or if I input 'ghhllz',what is the output?
Plz help me~

Why timelimit on 3rd test?
My program listing:

program hack;
var
ar : array[1..100] of byte;
i,n : integer;
word : string;
begin
readln(word);
n := length(word);
for i:=1 to n do
    begin
         ar[i] := ord(word[i]) - 97;
    end;

begin
      for i:=2 to n do
      begin
           if ar[i] < ar[i-1] then
           while ar[i] < ar[i-1] do ar[i]:= ar[i] + 26;
      end;
end;
for i:= 0 to n-2 do
    begin
         ar[n-i] := ar[n-i] - ar[n-i-1];
    end;
ar[1] := ar[1] - 5;

for i := 1 to n do
    begin
         word[i] := chr(97+ar[i]);
    end;

writeln(word);
end.