// PROBLEM 1 SOLVED:
/*
int odd_num_table ()
{
    int number;
    do
    {
        cout<<"Enter an uneven number bigger than 3 "<<endl<<"N = ";
        cin>>number;
    }while(number%2==0 || number <= 3 );

    for (int i=0;i<number;i++)
    {
        for (int j=0;j<number;j++)
        {
            if( (i==j) || (i+j == (number-1)) || i==(number-1)/2 || j==(number-1)/2 )
                cout<<"0";
            else
                cout<<"-";
            cout<<"\t";
        }
        cout<<endl<<endl;
    }
}
*/


// PROBLEM 2 SOLVED:
/*
int factorial(int n)
{
    if(n == 0 || n == 1)
      return 1;
    
    int product = 1;
    for(int i = 1 ; i <= n ; i++)
      product*=i;
    
    return product;
}

void show_addition_element(int coef, int x_pow, int y_pow)
{
     if(coef != 1) cout<<coef;
     
     if(x_pow > 1 ) cout<<"x^"<<x_pow;
     else if(x_pow == 1) cout<<"x";
     
     if(y_pow > 1 ) cout<<"y^"<<y_pow;
     else if(y_pow == 1) cout<<"y";
}

void newton_binom_formula()
{
     int pow;
     cout<<"Pow:"; cin>>pow;

     if(pow == 0)
     {
       cout<<1<<endl;
       system("PAUSE");
     }
         
         if(pow<0) cout<<"1/(";
         
         int iteration_pow = abs(pow);
         for(int i = 0 ; i <= iteration_pow ; i ++)
         {
            int coeficient = factorial(iteration_pow)/(factorial(i)*factorial(iteration_pow-i));
            int x_pow = iteration_pow - i;
            int y_pow = i;
                     
            show_addition_element(coeficient, x_pow, y_pow);
            if(i != iteration_pow) cout<<" + "; 
         }
         if(pow<0) cout<<")";
         cout<<endl;

}


// PROBLEM 3 SOLVED:
/*
    double r;

    do{
      cout<<"R="; cin>>r;
    }
    while(r<=0);
    
    for(int i = 3.5 - r ; i <= 3.5 + r ; i++)
    {
            for(int j = -r ; j <= r ; j++)
            {
               if((3.5-i)*(3.5-i) + j*j <= r*r)
               cout<<"["<<i<<", "<<j<<"]"<<endl;    
            }
    }
*/  

// PROBLEM 4 SOLVED:
/*
char start, end, swap;
do
{
     cout<<"Start:"; cin>>start;
     cout<<"End:"; cin>>end;
}while(abs(start-end) < 2);

if(start>end)
{ 
  swap = start;
  start = end;
  end = swap;
}

for(char i = start ; i <= end ; i++)
{
         for(char j = start ; j <= end ; j++)
         {
               for(char k = start ; k <= end ; k++)
               {
                     if((j-i) == (k-j))
                      cout<<i<<j<<k<<endl;
               }
         }
}
*/