UVa 12662 - Good Teacher

#include<bits/stdc++.h>

#define mx 110
using namespace std;

string str[mx];
int num[mx];

struct my
{
    int velo,posi;
};

my tmp[mx];

int BS(int lo, int hi, int itm)
{
    int mid;

    while(lo <= hi)
    {
        mid = (lo + hi) / 2;

        if(num[mid] == itm) return mid;
        else if(num[mid] > itm) hi = mid - 1;
        else if(num[mid] < itm) lo = mid + 1;
    }

    if(lo > hi) return -1;
    else return lo;
}

void Right(int n)
{
    for(int i=0; i<n; i++)
    {
        cout << "right of ";
    }
}

void Left(int n)
{
    for(int i=0; i<n; i++)
    {
        cout << "left of ";
    }
}

int main()
{
    ios_base::sync_with_stdio(false);

    int n;
    while(cin >> n)
    {
        int i , len=0 , pos=0;
        string s;

        for(i=1; i<=n; i++)
        {
            cin >> s;

            str[i] = s;

            if(s != "?")
            {
                len++;
                num[len] = i;
                pos = i;
            }
        }

        //cout << "len = " << len << "\n";
        //for(i=1; i<=n; i++) cout << str[i] << " ";
        int query;
        cin >> query;

        while(query--)
        {
            int srch;
            cin >> srch;

            int r = BS(1 , len, srch); //cout << r << "\n";

            if(srch == num[r])
            {
                cout << str[srch];
            }

            else
            {
                //r = BS(1 , len, srch); cout << r << "\n";

                int mini = 100000, epos=0, d=0 , pre=0, now=0 , tmplen=0;
                bool same=false;

                if(len > 1)
                {
                    for(i=1; i<=n; i++)
                    {
                        if(str[i] != "?")
                        {
                            tmplen++;
                            tmp[tmplen].posi = i;
                            tmp[tmplen].velo = abs(srch - i);

                            if(tmp[tmplen].velo == tmp[tmplen-1].velo)
                            {
                                same = true;
                                cout << "middle of " << str[tmp[tmplen-1].posi] << " and " << str[tmp[tmplen].posi];
                                break;
                            }
                        }
                    }

                    if(!same)
                    {
                        for(i=1; i<=n; i++)
                        {
                            if(str[i] != "?")
                            {
                                d = abs(srch - i);

                                if(d < mini)
                                {
                                    mini = d;
                                    epos = i;
                                }
                            }
                        }

                        if(srch < epos)
                        {
                            Left(mini);
                        }

                        else
                        {
                            Right(mini);
                        }

                        cout << str[epos];
                    }
                }

                else
                {
                    mini = abs(srch - pos);

                    if(srch < pos)
                    {
                        Left(mini);
                    }

                    else
                    {
                        Right(mini);
                    }

                    cout << str[pos];
                }
            }

            cout << "\n";
        }
    }

    return 0;
}