c++结构体解一元二次方程

以下是一个简单的 C++ 程序，可以用结构体来解一元二次方程：

#include <iostream>
#include <cmath>

using namespace std;

struct QuadraticEquation {
    double a, b, c;
};

int main() {
    QuadraticEquation eq;

    cout << "Enter the coefficients of the quadratic equation (ax^2 + bx + c = 0):" << endl;
    cout << "a = "; cin >> eq.a;
    cout << "b = "; cin >> eq.b;
    cout << "c = "; cin >> eq.c;

    double delta = eq.b * eq.b - 4 * eq.a * eq.c;

    if (delta > 0) {
        double x1 = (-eq.b + sqrt(delta)) / (2 * eq.a);
        double x2 = (-eq.b - sqrt(delta)) / (2 * eq.a);
        cout << "The equation has two real roots: x1 = " << x1 << ", x2 = " << x2 << endl;
    } else if (delta == 0) {
        double x = -eq.b / (2 * eq.a);
        cout << "The equation has one real root: x = " << x << endl;
    } else {
        double realPart = -eq.b / (2 * eq.a);
        double imagPart = sqrt(-delta) / (2 * eq.a);
        cout << "The equation has two complex roots: x1 = " << realPart << " + " << imagPart << "i, x2 = " << realPart << " - " << imagPart << "i" << endl;
    }

    return 0;
}

该程序使用 QuadraticEquation 结构体存储方程的系数，然后计算方程的根（如果有）。如果 delta 大于 0，则方程有两个实数根；如果 delta 等于 0，则方程有一个实数根；否则，方程有两个复数根。