萌新一个求大佬救一下

#include<bits/stdc++.h>
using namespace std;
int main()
{
	long L[3] = { 0 },mid=0;
	for (int i = 0; i <= sizeof(L) / sizeof(L[0])-1; i++)
	{
		cin >> L[i];
	}
	for (int i = 0; i <= sizeof(L) / sizeof(L[0])-1; i++)
	{
		for (int j = 0; j <= sizeof(L) / sizeof(L[0])-1; j++)
		{
			if ((L[i] < L[i + 1]))
			{
				mid = L[i + 1];
				L[i + 1] = L[i];
				L[i] = mid;
			}
		}
	}
	if ((L[0] + L[1] > L[2]) && (L[0] - L[1]< L[2]))
	{
		if (L[1] * L[1] + L[2] * L[2] == L[0] * L[0])
		{
			cout << "Right triangle" << endl;//直角
		}
		else if (L[1] * L[1] + L[2] * L[2] > L[0] * L[0])
		{
			cout << "Acute triangle" << endl;//锐角
		}
		else
		{
			cout << "Obtuse triangle" << endl;//钝角
		}
		if ((L[1] == L[2]) || (L[1] == L[0]) || (L[2] == L[0]))
		{
			if ((L[1] == L[2]) && (L[2] == L[0]))
			{
				cout << "Equilateral triangle" << endl;//等边
			}
			cout << "Isosceles triangle" << endl;//等腰
		}
	}
	else
		cout << "Not triangle" << endl;//不成立
	return 0;
}

第一次发帖 不会用 先谢谢大佬解答~