One knight

The hungry chess knight stays in the cell (x[1], y[1]) of the chessboard of size n × n. He wants to get into the cell (x[2], y[2]), where delicious chess grass grows. What is the least number of moves he has to do?

Input

Contains five numbers: n, x[1], y[1], x[2], y[2] (5 ≤ n ≤ 20, 1 ≤ x[1], y[1], x[2], y[2] ≤ n). The upper left cell of the board has coordinates (1, 1), the bottom right - (n, n).

Output

Print the minimum number of moves to go from (x[1], y[1]) to (x[2], y[2]).

Examples