範例程式碼 uva10242

//uva10242
#include <stdio.h>
#include <algorithm>
#include <string.h>

using namespace std;

int main(void) {
    double x1, y1, x2, y2, x3, y3, x4, y4;

    while(scanf("%lf %lf %lf %lf %lf %lf %lf %lf", &x1, &y1, &x2, &y2, &x3, &y3, &x4, &y4)!= EOF) {
        if(x1 == x3 && y1 == y3)
            printf("%.3lf %.3lf\n", (x2 + x4) - x1, (y2 + y4) - y1);
        else if(x1 == x4 && y1 == y4)
            printf("%.3lf %.3lf\n", (x2 + x3) - x1, (y2 + y3) - y1);
        else if(x2 == x3 && y2 == y3)
            printf("%.3lf %.3lf\n", (x1 + x4) - x2, (y1 + y4) - y2);
        else
            printf("%.3lf %.3lf\n", (x1 + x3) - x2, (y1 + y3) - y2);
    }
    return 0;
}