Untitled

#include <bits/stdc++.h>
using namespace std;

int main()
{
	float a,b,c;
	cin >> a >> b >> c;

	//Neu khong phai tam giac
	if (a+b<=c || b+c<=a || a+c<=b)
	{
		cout <<"Khong phai la 3 canh tam giac. \n";
	}

	//Kiem tra co phai la tam giac
	if (a+b>c && b+c>a && a+c>b)
	{
		//Kiem tra tam giac deu
		if (a==b && a==c)
		{
			float cv = a+b+c;
			float p = cv/2;
			float dt = sqrt((p*(p-a)*(p-b)*(p-c)));
			cout <<"Tam giac deu \n";
			cout <<"Chu vi = " << cv << endl;
			cout <<"Dien tich = " << dt << endl;
		}

		//Kiem tra tam giac can
		if (a==b || b==c || a==c)
		{
			float cv = a+b+c;
			float p = cv/2;
			float dt = sqrt((p*(p-a)*(p-b)*(p-c)));
			cout <<"Tam giac can \n";
			cout <<"Chu vi = " << cv << endl;
			cout <<"Dien tich = " << dt << endl;
		}

		//Kiem tra tam giac tu
		if (a*a > b*b + c*c || b*b > a*a+ c*c || c*c > a*a + b*b)
		{
			float cv = a+b+c;
			float p = cv/2;
			float dt = sqrt((p*(p-a)*(p-b)*(p-c)));
			cout <<"Tam giac tu \n";
			cout <<"Chu vi = " << cv << endl;
			cout <<"Dien tich = " << dt << endl;
		}

		//Kiem tra tam giac vuong
		if (a*a == b*b + c*c || b*b == a*a+ c*c || c*c == a*a + b*b)
		{
			float cv = a+b+c;
			float p = cv/2;
			float dt = sqrt((p*(p-a)*(p-b)*(p-c)));
			cout <<"Tam giac vuong \n";
			cout <<"Chu vi = " << cv << endl;
			cout <<"Dien tich = " << dt << endl;

		//Khong thoa man tat ca dieu kien tren thi la tam giac nhon
			float cv = a+b+c;
			float p = cv/2;
			float dt = sqrt((p*(p-a)*(p-b)*(p-c)));
			cout <<"Tam giac nhon \n";
			cout <<"Chu vi = " << cv << endl;
			cout <<"Dien tich = " << dt << endl;
		}
	} 
	
	return 0;
}