C语言（unix）

/* triangle.c */
//---------------------------------------------------------------------------

#include <stdio.h>
int can(int,int,int);
void equilateral(int,int,int);
void isosceles(int,int,int);
void RightAngled(int,int,int);

int main(int argc, char* argv[])
{
int a,b,c;
scanf("%d%d%d",&a,&b,&c);
printf("%s\n%s\n%s\n%s\n\n",
"Can a triangle can be formed with the given lengths?",
"Is the triangle equilateral?" ,
"If the triangle is not equilateral, it is isosceles?",
"Is the triangle right-angled?");

if (can(a,b,c))puts("Yes");
else puts("No");
equilateral(a,b,c);
isosceles(a,b,c);
RightAngled(a,b,c);

return 0;
}
int can(int a,int b,int c)
{
if (a+b>c&&a-b<c)
return 1;