#include<stdio.h> #include <math.h> #define PI 3.14159265 int main() { int n; scanf("%d",&n); double x1,x2,y1,y2; for(int i=0;i<n;i++){ scanf("%lf%lf%lf%lf",&x1,&y1,&x2,&y2); double len1=sqrt(x1*x1+y1*y1),len2=sqrt(x2*x2+y2*y2);//两个角相减 printf("%.2lf\n",fabs(acos(x1/len1)-acos(x2/len2))*(180/PI)); //因为acos(x)函数返回弧度区间为 [0, pi]。所以要转化为角度 } return 0; }
0.0分
1 人评分