#include?<stdio.h>
int?getGirth(int?a,int?b,int?c)
{
????if(?(a+b)<=c?||?(a+c)<=b?||?(b+c)<=a?)???//判斷是否為三角形
????{
????????printf("不構成三角形\n");
????????return?0;????????????????????????????????
????}
????else
????{
??????int?cirf?=a+b+c?;?????//計算三角形周長
??????return?cirf;
????}
???????
}
int?main()
{
????/*?定義三角形三邊長?*/
????int?a,?b,?c;
????a?=?3;
????b?=?4;
????c?=?5;
????printf("三角形的周長是：%d\n",getGirth(a,b,c));??//調用周長函數
????return?0;
}

第二十三行的函數別自己把數字放進去，用給的a.b.c，給的有賦值了，所以能得出答案12