ม้าหมากรุก ACM-ICPC Online 2012

// ACM-ICPC Online 2012 ม้าหมากรุก
#include<iostream>
#include<algorithm>
#include<sstream>
#include<fstream>
#include<utility>
#include<cstdlib>
#include<cstring>
#include<string>
#include<bitset>
#include<vector>
#include<cstdio>
#include<cctype>
#include<cmath>
#include<queue>
#include<deque>
#include<stack>
#include<map>
#include<climits>
#include <utility>
#define ll long long
#define p cout
#define s cin
#define pi 2*acos(0.0)
#define fuck INT_MAX
using namespace std;
void ch(int i,int j,int a[100][100],int N)
{
 if(a[i-2][j+1]==fuck && i-2>=1 && j+1<=N)
    a[i-2][j+1]=a[i][j]+1;

 if(a[i-2][j-1]==fuck && i-2>=1 && j-1>=1)
    a[i-2][j-1]=a[i][j]+1;

 if(a[i+2][j+1]==fuck && i+2<=N && j+1<=N)
    a[i+2][j+1]=a[i][j]+1;

if(a[i+2][j-1]==fuck && i+2<=N && j-1>=1)
     a[i+2][j-1]=a[i][j]+1;

 if(a[i-1][j+2]==fuck && i-1>=1 && j+2<=N)
   a[i-1][j+2]=a[i][j]+1;

 if(a[i-1][j-2]==fuck && i-1>=1 && j-2>=1)
    a[i-1][j-2]=a[i][j]+1;

 if(a[i+1][j+2]==fuck && i+1<=N && j+2<=N)
    a[i+1][j+2]=a[i][j]+1;

 if(a[i+1][j-2]==fuck && i+1<=N && j-2>=1)
    a[i+1][j-2]=a[i][j]+1;

}
int main()
{
    int N,M,P;
    short number1,number2;

    while(1)
    {
        s >> N >> M >> P;
        if(N==0 && M==0 && P==0)
            break;
        int a[100][100];

        vector<pair<int,int> > v ;
        v.push_back(make_pair(0,0));

        vector<pair<int,int> > v1 ;
        v1.push_back(make_pair(0,0));

        for(short i=0;i<=M;i++)
        {
            s >> number1 >> number2;
            v.push_back(make_pair(number1,number2));
        }

        for(short i=0;i<P;i++)
        {
            s >> number1 >> number2;
            v1.push_back(make_pair(number1,number2));
        }

        for(short i=1;i<=N;i++)
        {
            for(short j=1;j<=N;j++)
            {
                if(v[1].first==i && v[1].second==j)
                        a[i][j]=0;
                else  a[i][j]=fuck;
            }
        }


        for(int k=0;k<=N;k++)
        {
            for(int i=1;i<=N;i++)
            {
                for(int j=1;j<=N;j++)
                {
                    if(a[i][j]==k)
                        ch(i,j,a,N);
                }
            }
        }
        for(int i=1;i<=M;i++)
            a[v[i].first][v[i].second]=-1;

        for(int i=1;i<v1.size();i++)
        {
                cout << a[v1[i].first][v1[i].second]<<endl;
        }

    }




}