#include <stdio.h>
int main()
{
int a,b,c;
int A,B,C;
A=(b*b+c*c-a*a)/(2*b*c);
B=(a*a+c*c-b*b)/(2*a*c);
C=(b*b+a*a-c*c)/(2*b*a);
scanf("%d %d %d",&a,&b,&c);
if ( a+b<=c||a+c<=b||b+c<=a ){
printf("Not triangle");
}else{
if ( a*a+b*b==c*c||a*a+c*c==b*b||b*b+c*c==a*a ){
printf("Right triangle");
}else if ( A>0&&B>0&&C>0 ){
printf("Acute triangle");
}else if ( A<0||B<0||C<0 ){
printf("Obtuse triangle");
}
}
if ( (a==b&&a!=c)||(a==c&&a!=b)||(b==c&&b!=a) ){
printf("Isosceles triangle");
}else if ( a==b&&a==c&&b==c ){
printf("Equilateral triangle");
}
return 0;
}
感觉没大问题啊