@startuml flowchart
title 三角形分类程序流程图 — classify(a, b, c)

start

:输入三条边 a, b, c;

if (a <= 0 || b <= 0 || c <= 0 ?) then (是)
  :返回 NOT_A_TRIANGLE;
  stop
else (否)
endif

if ((long)a+b <= c ||\n(long)a+c <= b ||\n(long)b+c <= a ?) then (是)
  :返回 NOT_A_TRIANGLE;
  stop
else (否)
endif

if (a == b && b == c ?) then (是)
  :返回 EQUILATERAL\n(等边三角形);
  stop
else (否)
endif

if (a == b || b == c || a == c ?) then (是)
  :返回 ISOSCELES\n(等腰三角形);
  stop
else (否)
  :返回 SCALENE\n(一般三角形);
  stop
endif

@enduml