In UDebug of this problem,there is one invalid input case for which this code will show wrong output, but actually that input case is invalid for this problem !! So don’t bother with the UDebug output, this code will be Accepted in UVa OJ.

The invalid input is P==0 && L==0. If you put the following line in the following code

if(P==0 && L==0) pf(“1”);

then your code will pass all the inputs in UDebug & you will get AC. But without putting this line, you will also get an 100% legal AC :p Since this code is for all valid inputs !! 😀

#include <bits/stdc++.h>

#define pf                  printf
#define sf(a)               scanf("%d",&a)
#define sfl(a)              scanf("%lld",&a)
#define sff(a,b)            scanf("%d %d",&a,&b)
#define sffl(a,b)           scanf("%lld %lld",&a,&b)
#define sfff(a,b,c)         scanf("%d %d %d",&a,&b,&c)
#define sfffl(a,b,c)        scanf("%lld %lld %lld",&a,&b,&c)
#define sffff(a,b,c,d)      scanf("%d %d %d %d",&a,&b,&c,&d)
#define sffffl(a,b,c,d)     scanf("%lld %lld %lld %lld",&a,&b,&c,&d)
#define sfffff(a,b,c,d,e)   scanf("%d %d %d %d %d",&a,&b,&c,&d,&e)
#define sfffffl(a,b,c,d,e)  scanf("%lld %lld %lld %lld %lld",&a,&b,&c,&d,&e)
#define ms(a,b)             memset(a,b,sizeof(a))
#define pb(a)               push_back(a)
#define db                  double
#define ft                  float
#define ll                  long long
#define ull                 unsigned long long
#define ff                  first
#define ss                  second
#define sz(x)               x.size()
#define qu                  queue
#define pqu                 priority_queue
#define vc                  vector
#define vi                  vector<int>
#define vll                 vector<long long>
#define pii                 pair<int,int>
#define pis                 pair<int,string>
#define psi                 pair<string,int>
#define all(x)              x.begin(),x.end()
#define CIN                 ios_base::sync_with_stdio(0); cin.tie(0)
#define max3(a, b, c)       max(a, b) > max(b, c) ? max(a, b) : max(b, c)
#define min3(a, b, c)       min(a, b) < min(b, c) ? min(a, b) : min(b, c)
#define loop0(i,n)          for(int i=0;i<n;i++)
#define loop1(i,n)          for(int i=1;i<=n;i++)
#define loopab(a,b)         for(int i=a;i<=b;i++)
#define stlloop(x)          for(__typeof(x.begin()) it=x.begin();it!=x.end();it++)
#define gcd(a, b)           __gcd(a, b)
#define lcm(a, b)           ((a)*((b)/gcd(a,b)))
#define case1(z)            cout<<"Case "<<z<<": "
#define case2(z)            printf("Case %d: ",z)
#define PI                  3.14159265358979323846264338328
#define valid(tx,ty)        tx>=0 && tx<r && ty>=0 && ty<c
#define intlim              2147483648
#define MAX                 2000
#define inf                 10000000

/*------------------------------Graph Moves----------------------------*/
//const int fx[]={+1,-1,+0,+0};
//const int fy[]={+0,+0,+1,-1};
//const int fx[]={+0,+0,+1,-1,-1,+1,-1,+1};   // Kings Move
//const int fy[]={-1,+1,+0,+0,+1,+1,-1,-1};  // Kings Move
//const int fx[]={-2, -2, -1, -1,  1,  1,  2,  2};  // Knights Move
//const int fy[]={-1,  1, -2,  2, -2,  2, -1,  1}; // Knights Move
/*---------------------------------------------------------------------*/

using namespace std;

vector<int> v1,v2;

void generating_divisor(int n, int L)
{
    for(int i=1; i<=sqrt(n); i++)
    {
        if(n%i==0)
        {
            if(n/i==i && i>L ) v1.pb(i);
            else
            {
                if(i>L) v1.pb(i);
                if(n/i>L) v2.pb(n/i);
            }
        }
    }
}

int main()
{
    //CIN;
//    freopen("in.txt","r",stdin);
//    freopen("out.txt","w",stdout);
    int t;
    sf(t);
    loop1(z,t)
    {
        int P,L;
        scanf("%d %d",&P,&L);
        int n=P-L;
        generating_divisor(n,L);
        case2(z);
        //if(P==0 && L==0) pf("1"); // eta Udebug er invalid input, eta dileo AC , na dileo AC,but eta valid input na
        if(sz(v1)==0 && sz(v2)==0) pf("impossible");
        else
        {

            if(sz(v1)>0)
            {
                pf("%d",v1[0]);
                for(int i=1; i<sz(v1); i++) pf(" %d",v1[i]);
            }
            if(sz(v2)>0)
            {
                if(sz(v1)>0)
                {
                    for(int i=sz(v2)-1; i>=0; i--) pf(" %d",v2[i]);
                }
                else
                {
                    pf("%d",v2[sz(v2)-1]);
                    for(int i=sz(v2)-2; i>=0; i--) pf(" %d",v2[i]);
                }
            }
        }
        pf("\n");
        v1.clear();
        v2.clear();
    }
    return 0;
}