백준 10101 c++

#include <iostream>
using namespace std;

int input(int lower, int upper);
void input_arr(int* arr, int row);
void check_triangle(int* arr, int row);

int main(void)
{
	int arr[3];
	
	input_arr(arr, 3);
	check_triangle(arr, 3);

	return 0;
}

int input(int lower, int upper)
{
	int A;

	while (1)
	{
		cin >> A;
		if (A >= lower && A <= upper)
		{
			break;
		}
		else
		{
			;
		}
	}

	return A;
}

void input_arr(int* arr, int row)
{
	int i;

	for (i = 0; i < row; i++)
	{
		arr[i] = input(1, 179);
	}

	return;
}

void check_triangle(int* arr, int row)
{
	int A = arr[0], B = arr[1], C = arr[2];
	if ((A+B+C) != 180)
	{
		cout << "Error" << endl;
	}
	else
	{
		if (A == 60 && B == 60 && C == 60)
		{
			cout << "Equilateral" << endl;
		}
		else if (A == B || B == C || C == A)
		{
			cout << "Isosceles" << endl;
		}
		else
		{
			cout << "Scalene" << endl;
		}
	}

	return;
}