I CAN'T GET ACCEPTED A HALF OF THE YEAR. I DON'T KNOW, WHAT
I DO WRONG.
HERE IS MY SYMPLE C++ PROGRAMM:



#include <iostream.h>

const Nmax = 8000; // 7500;

int N;
int a[Nmax];
int i1[Nmax];
int i2[Nmax];

void Solve();

void main()
{
    int i,j;

    N = 1;

    do
    {
        if (cin.eof())
            break;

        cin >> a[N];
        a[N++] --;
    } while (1);

    N--;

    Solve();
    int b[Nmax];
    int k;

    for (int ii=0; ii<N; ii++)
    {
        cout << ii+1 << ":";
        k = 0;

        for (j=0; j<N-1; j++)
        {
            if (i1[j]==ii)
                b[k++] = i2[j]+1;
            else
            if (i2[j]==ii)
                b[k++] = i1[j]+1;
        }

        for (i=0; i<k-1; i++)
            for (j=i+1; j<k; j++)
                if (b[i]>b[j])
                {
                    int t = b[i];
                    b[i] = b[j];
                    b[j] = t;
                }

        for (i=0; i<k; i++)
            cout << " " << b[i];

        cout << endl;
    }
}

void Solve()
{
    int i,j;
    int c[Nmax];

    for (i=0; i<N; i++)    c[i] = 0;
    c[a[N-1]] = 1;

    int k = 0;

    for (i=N-1; i>=0; i--)
    {
        if (i>0 && !c[a[i-1]])
        {
            c[a[i-1]] = 1;
            i1[k] = a[i-1];
            i2[k++] = a[i];
        } else
        {
            for (j=N-1; j>=0; j--)
                if (!c[j])
                {
                    c[j] = 1;
                    i1[k] = j;
                    i2[k++] = a[i];
                    break;
                }
        }
    }
}



THANK YOU !