what is answer for that test
5 -9
4 -8 -6 1 -10
?

var
b,a,i,c,n,d,an,k,x:integer;  // many variables from other programms...
dev:boolean;
s:string;
begin
read(k,n);
dev:=true;
b:=1001;
//didn't no about abs
if n<0 then x:=-1;
if n>0 then x:=1;
for i:=1 to k do
begin
read(a);
if (0<a*x) and (a*x<n*x) and dev then begin s:=('Impossible'); dev:=false end; // can't reach the end
if abs(a)<b then b:=abs(a);      //nearest obsacle to start point
end;
if dev then // output
begin
if n>0 then writeln(n,' ',n+b*2);
if n<0 then writeln(abs(n)+2*b,' ',abs(n));
end
else
writeln(s);
end.




**********Can't understand what's wrong************

This is my code:

#include <iostream>
#include <cmath>

using namespace std;
int main()
{
    int a[101], n, x, dis1 = 0, dis2 = 0, lb, rb;
    bool flag = false, flag2 = false;

    cin >> n >> x;

    if ((x == 0))
      flag2 = true;
    else
    {
      if ( n == 0 )
        flag = true;
    }

    for ( int i = 0; i < n; i++ )
    {
      cin >> a[i];
      if ( (x > 0) && (a[i] < x) && (a[i] > 0) )
        flag = true;

      if ( (x < 0) && (a[i] > x)  && (a[i] < 0) )
        flag = true;
    }

    if (flag)
      cout << "Impossible" << endl;
    else
    {
      lb = a[0];
      rb = a[0];
      for ( int i = 1; i < n; i++ )
      {
        if ( (a[i] > 0) && (a[i] > rb) && (a[i] > x) )
          rb = a[i];

        if ( (a[i] < 0) && (abs(a[i]) < abs(lb)) && (a[i] < x) )
          lb = a[i];
      }

      if ( x > 0 )
      {
        dis1 = x;
        dis2 = (int) abs(2*lb) + x;
      }
      else
      {
        dis1 = 2*rb + (int) abs(x);
        dis2 = (int) abs(x);
      }

      if (flag2)
        cout << "0 0" << endl;
      else
        cout << dis1 << " " << dis2 << endl;
    }

    system("PAUSE");
    return 0;
}

---------------------------
I can't understand WHY WA#4
Please, help!!!

who could give some testdata to me ?


3  3
9
10
11

result?

Edited by author 05.11.2008 04:11

In the example test:
3 -2
10 -1 2
It's not Impossible.

to the right first:
2 + 2 + 1 + 1 + 10 + 10 + 2 (reached -2, got answer) = 28
to the left:
1 + 1 + 2 + 2 + 2 (reached -2, got answer) = 8
answer:
28 8

Test 3 :
input :
5 2
-1 -2 -3 -4 -5
output :
2 4

Test 4 :
input :
2 0
1 -5
output :
0 0

Test 5 :
input :
15 23
252 33 215 789 1000 123 -125 29 -45 -450 121 -555 -72 120 123
output :
23 113

Test 6 :
0 213
output
Impossible

Test 7 :
input :
8 12
1 2 3 4 5 6 7 8
output :
Impossible

Test 10 :
input :
0 0
output :
0 0

Test 15 :
input :
2 12
1000 -1000
output :
12 2012

Try this:
1 1 -1

ans: 1 3

#include<stdio.h>
int n,i,exit,leftob=-1005,rightob=1005,temp;
main()
{
      scanf("%d %d",&n,&exit);

      for (i=0;i<n;i++)
      {
          scanf("%d",&temp);
          if (temp<rightob && temp>exit)
             rightob=temp;
          if (temp>leftob && temp<exit)
             leftob=temp;
      }

      if (leftob==-1005)
         leftob=exit;
      if (rightob==1005)
         rightob=exit;

      if (exit>0)
      {
         if (leftob>0)
            printf("Impossible\n");
         else
             printf("%d %d\n",exit,-2*leftob+exit);
      }
      else
      {
          if (rightob<0)
             printf("Impossible\n");
          else
              printf("%d %d\n",2*rightob-exit,-exit);
      }
      scanf(" ");
}

Please give test number 9. And as much as possible tests.

#include<iostream>
#include<vector>
using namespace std;
int main()
{
     int n,x,m=0,k=0,g;
     cin>>n>>x;
    vector<int> a(n);
    if(n==1)
    {
        cin>>g;
        if(g<0&&x>0)
        {
            cout<<x<<" "<<-2*g+x;
        }
        else if(g>0&&x<0)
        {
              cout<<2*g-x<<" "<<-x;
        }
        else
        cout<<"Impossible";
    }
    else
     {
        for(int i=0;i<n;i++)
          {
            cin>>a[i];
            if(a[i]<x&&m==0)
            m=a[i];
            else if(a[i]<x&&a[i]>m&&m!=0)
            m=a[i];
            else if(a[i]>x&&k==0)
            k=a[i];
            else if(a[i]>x&&k!=0&&a[i]<k)
            k=a[i];
        }
        if(m<0&&k>0)
         {
            if(x<0)
            cout<<2*k-x<<" "<<-x;
            else
            cout<<x<<" "<<-2*m+x;
        }
        else if(m<0&&k==0&&x>0)
        {
               cout<<x<<" "<<2*x-m;
        }
        else if(k>0&&m==0&&x<0)
        {
            cout<<2*k-x<<" "<<-x;
        }
        else
        cout<<"Impossible";
     }

    return 0;
}

My python 2.6 code:
============
#!/usr/bin/python
import sys

def getDist(path,pr,pl):
    global x
    coord = 0
    i = 0
    if path == 1:
        pp = 1
    else:
        pp = -1
    while coord != x:
        if pp == 1:
            try:
                bord = pr.pop(0)
            except:
                bord = None
        else:
            try:
                bord = pl.pop(0)
            except:
                bord = None
        while coord != bord :
            coord +=  pp
            i += 1
            if coord == x:
                break
        pp *= -1
    return i

(n,x) = (int(x) for x in sys.stdin.readline().rstrip().split(" "))
p = [int(j) for j in sys.stdin.readline().split()]
p.sort()
pr = []
pl = []
for i in xrange(len(p)):
    if p[i] >= 0:
        pr.append(p[i])
    else:
        pl.append(p[i])
pl.reverse()
dist = 0
if pr == []:
    pr = [1000]
if pl == []:
    pl = [-1000]
if x > max(pr) or x < min(pl):
    print  "Impossible"
else:
    print getDist(1,pr,pl), getDist(-1,pr,pl)
===========

Another test's on forum is OK

What input data on test 7?

Edited by author 02.02.2013 13:33

Please, give some testdata

Edited by author 06.04.2009 19:06

var
n,i,k:byte;
x,d,y:integer;
m:array[0..100] of integer;
begin
read(n,x);
for i:=1 to n do
read(m[i]);
k:=0;
y:=n;

if x<0 then begin

for i:=1 to y do begin
if (m[i]>x) and (m[i]<0) then
begin writeln('Impossible'); k:=k+1;end
else
begin if m[i]<0 then begin y:=abs(x); end;
if m[i]>0 then d:=m[i];
end;
if m[i]<d then d:=m[i];end;
writeln(d+d+abs(x));
writeln(y);

end;

if x>0 then begin
for i:=1 to n do begin
if (m[i]<x) and (m[i]>0) then begin writeln('Impossible'); k:=k+1;end
else
begin if (m[i]>x) and (m[i]>0) then begin d:=x; writeln(d);end;
if m[i]<0 then d:=m[i];end;
if (m[i]<0) and (m[i]>d) then d:=m[i];
end;
writeln(abs(d)+abs(d)+x);
end;




end.

why?

#include <iostream>
#include <cmath>
using namespace std;
#define SWAP(A, B) { int t = A; A = B; B = t; }

void bubblesort(int *a, int n)
{
  int i, j;

  for (i = n - 1; i > 0; i--)
  {
    for (j = 0; j < i; j++)
    {
      if (a[j] > a[j + 1])
        SWAP( a[j], a[j + 1] );
    }
  }
}
int main()
{
int n,x,ar[100];
cin>>n>>x;
for(int i=0;i<n;i++)
cin>>ar[i];
bubblesort(ar,n);
int j=0;
while(ar[j]<0 && j<n-1)
    ++j;
if(ar[j-1]<x && ar[j]>x && n!=1 )
{
    if(x<0)
    cout<<2*ar[j]-x<<" "<<0-x;
    else
        cout<<x<<" "<<abs(2*ar[j-1])+x;
}
else
    if(n==1)
    {
    if(ar[0] > x)
        cout<<2*abs(ar[0])-x<<" "<<-x;
    else
        cout<<x<<" "<<2*abs(ar[0])+x;
    }
    else
    cout<<"Impossible";
}

tell me somebody please what in this test?

for example , what's the output for this test?
input:
0 1