上线全WA，本地没问题，不知道为啥，

zhifangzi @ 2021-09-07 23:25:03

#include <iostream>
#include<iomanip>
#include<math.h>

using namespace std;

class point
{
public:
     bool set(double a, double b);
     point();
     point(double x, double y);
     double reflex(int deter);
private:
    double x, y;
};
double distance(double x1, double x2, double y1, double y2);

int main()
{
    point a[3];
    for (int i = 0; i <= 2; i++)
    {
        double x, y;
        cin >> x ;
        cin >> y;

        a[i].set(x, y);
    }
    double dis=0;

    for (int i = 0; i <= 2; i++)
    {
        if (i <2)
        {
            dis=dis+distance(a[i].reflex(1), a[i + 1].reflex(1), a[i].reflex(2), a[i + 1].reflex(2));

        }
        if (i == 2)
        {
            dis=dis+distance(a[i].reflex(1), a[0].reflex(1), a[i].reflex(2), a[0].reflex(2));

        }

    }
    printf("%.2llf", dis);
    return 0;
}

point::point(double a, double b)
{
    x = a;
    y = a;
 }
point::point()
{
    x = 0;
    y = 0;

}
bool point::set(double a, double b)
{
    x = a;
    y = b;
    return true;
}
double point::reflex(int deter)
{
    if (deter == 1)
    {
        return x;
    }
    else
    {
        return y;
    }
}

double distance(double x1,double x2,double y1,double y2)
{
    double aa = (x1 - x2);
    double bb = y1 - y2;
    double result = sqrt(aa * aa + bb * bb);
    return result;
}

by zhifangzi @ 2021-09-07 23:31:56

我想骂人， 破案了，最后需要scanf里面写lf而非llf 这个怎么写vs都能出来，洛谷不行，

吐血 一晚上浪费了

附上过了的代码：

#include <iostream>
#include<iomanip>
#include<math.h>
#define _CRT_SECURE_NO_WARNINGS

using namespace std;

class point
{
public:
     bool set(double a, double b);
     point();
     point(double x, double y);
     double reflex(int deter);
private:
    double x, y;
};
double distance(double x1, double x2, double y1, double y2);

int main()
{
    point a[3];
    for (int i = 0; i <= 2; i++)
    {
        double x, y;
        cin >> x ;
        cin >> y;

        a[i].set(x, y);
    }
    double dis=0;

    for (int i = 0; i <= 2; i++)
    {
        if (i <2)
        {
            dis=dis+distance(a[i].reflex(1), a[i + 1].reflex(1), a[i].reflex(2), a[i + 1].reflex(2));

        }
        if (i == 2)
        {
            dis=dis+distance(a[i].reflex(1), a[0].reflex(1), a[i].reflex(2), a[0].reflex(2));

        }

    }
    printf("%.2llf", dis);
    return 0;
}

point::point(double a, double b)
{
    x = a;
    y = a;
 }
point::point()
{
    x = 0;
    y = 0;

}
bool point::set(double a, double b)
{
    x = a;
    y = b;
    return true;
}
double point::reflex(int deter)
{
    if (deter == 1)
    {
        return x;
    }
    else
    {
        return y;
    }
}

double distance(double x1,double x2,double y1,double y2)
{
    double aa = (x1 - x2);
    double bb = y1 - y2;
    double result = sqrt(aa * aa + bb * bb);
    return result;
}

by ud2_ @ 2021-09-08 00:13:51

所以换个编译器吧。

GCC 的编译警告：

main.cpp: In function 'int main()':
main.cpp:46:18: warning: use of 'll' length modifier with 'f' type character has either no effect or undefined behavior [-Wformat=]
   46 |     printf("%.2llf", dis);
      |                  ^
main.cpp: In constructor 'point::point(double, double)':
main.cpp:50:31: warning: unused parameter 'b' [-Wunused-parameter]
   50 | point::point(double a, double b)
      |                        ~~~~~~~^

by Blackajactic @ 2021-09-08 11:46:15

devc++用吧，vs是vc，不一样的

by 2022fsjh @ 2022-08-05 09:56:06

的确，呵呵