View Code of Problem 106

#include<stdio.h>
#include<math.h>

int main()
{
    double x1,x2,y1,y2,r;
    while(scanf("%lf%lf%lf%lf%lf",&x1,&y1,&x2,&y2,&r) != EOF)
    {
        double s,a,z;
        //s = sqrt(pow(x2 - x1, 2) + pow(y2 - y1, 2));
        //s = sqrt(pow(x2-x1,2) + pow(y2-y1,2));
        s = sqrt((x2-x1)*(x2-x1) + (y2-y1)*(y2-y1));
        //printf("%.2lf\n",s);
        if(s == 2*r)
            printf("相切\n");
        else if((x1 == x2) && (y1 == y2))
            printf("重合\n");
        else if(s > 2*r)
            printf("相离\n");
        else
        {
            printf("相交 ");
            z = acos(s / (2*r));
            a = 2 * r * r * z - s * r * sin(z);
            printf("%.2lf\n",a);
        }
    }
}