judgement triangle

Problem Statement

One day, Zzy was doing her homework and came across a difficult problem. What did the puzzle look like? Given three coordinate points $(X_a,Y_a,X_b,Y_b,X_c,Y_c)$, find whether the triangle is a right triangle, an acute triangle, or an obtuse triangle. Note1:These three coordinate points must be able to form a triangle Note2:If the triangle also contains an acute triangle then output a right triangle. Can you help him solve this problem?

Constraints

• $-1000 \leq X_a, Y_a, X_b, Y_b, X_c, Y_c \leq 1000$
• The three points $A$, $B$, and $C$ are not collinear.
• All input values are integers.

Standard input

The input is given from Standard Input in the following format:

$X_a,Y_a$ $X_b,Y_b$ $X_c,Y_c$

Output

Given three coordinate points$(X_a,Y_a,X_b,Y_b,X_c,Y_C)$, find whether the triangle is a right, acute or obtuse triangle.

Output acute triangle or right angled triangle or obtuse triangles

Sample calendar

Sample Input 1

0 0
4 0
0 3

Sample Output 1

right angled triangle

Sample Input 2

2 4
-3 2
1 -2

Sample Output 2

acute triangle

Sample Input 3

2 7
2 1
6 3

Sample Output 3

obtuse triangles

题面翻译

给定三个坐标点$（X_a,Y_a,X_b,Y_b,X_c,Y_c）$，求这个三角形是直角三角形、锐角三角形还是钝角三角形。 如果是锐角三角就输出acute triangle 直角就输出right angled triangle 钝角就输出obtuse triangles