如上输入，导致输出（按理来说，不应该输出Isosecels triangle）

Acute triangle

Isosceles triangle

Equilateral triangle

// 余弦定理 // 排序

#include <iostream>
#include <algorithm>
#include <vector>
#include <cmath>

using namespace std;

int main()
{

    // Input data

    // Output data
    int a, b, c;
    cin >> a >> b >> c;
    vector<int> nums = {a, b, c};
    sort(nums.begin(), nums.end());
    if (nums[0] + nums[1] <= nums[2])
    {
        cout << "Not triangle" << endl;
    }
    else
    {
        int middle = pow(nums[0], 2) + pow(nums[1], 2);
        if (middle > pow(nums[2], 2))
        {
            cout << "Acute triangle" << endl;
        }

        else
        {
            if (middle == pow(nums[2], 2))
            {
                cout << "Right triangle" << endl;
            }
            else
            {
                cout << "Obtuse triangle" << endl;
            }
        }

        if (a == b && b == c)
        {
            cout << "Equilateral triangle" << endl;
            return 0;
        }
        else
        {
            if (a == b || b == c || a == c)
            {
                cout << "Isosceles triangle" << endl;
            }
        }
    }

    return 0;
}