#include <iostream>
#include <cmath>

int main() {
    // 计算角度为45度的正切值（角度需要转换为弧度）
    double angleInDegrees = 45.0;
    double angleInRadians = angleInDegrees * (M_PI / 180.0); // 将角度转换为弧度
    double tanValue = tan(angleInRadians);

    // 输出结果
    std::cout << "Tangent of " << angleInDegrees << " degrees is: " << tanValue << std::endl;

    return 0;
}