Double attack
Problem
Willie went even further. Now he decided to write a program that will tell him whether there is a double attack on the board (that is, whether any piece threatens the other two). But Willy has little time, now he is preparing for the next competition. He asks you to help him write a draft for his program. You need to determine from the coordinates of the figures whether the bishop threatens the other two figures or not.
Input: the input program receives three lines with two numbers. The first number in the line is the vertical number, the second horizontal number. The first line contains the coordinates of the bishop (one color). In the second and third coordinates of two other figures (in a different color). All figures are in different fields.
Output: output the word "double" if the bishop threatens two other figures, otherwise output the word "no"
Example
Input
4 4
5 5
6 6
Output
double
Запрещенные операторы: for; while; until