UESTC1713 無關青雲路,無關詩書,無你處,無江湖
阿新 • • 發佈:2017-07-23
return tdi math out std spa ble ret blog
題意:給出兩個圓的坐標求兩圓相交的面積
題解:兩個圓相交,包含,相離,相切等情況,判斷兩個圓心的距離與半徑的關系,相交的部分可以看作是兩個扇形減去菱形的面積
#include <stdio.h> #include <math.h> #define PI acos(-1) double x1,x2,yy,y2,R,r,s1,s2,p,s3,l, s5,s4; int main(){ int T; scanf("%d", &T); while(T--){ scanf("%lf%lf%lf%lf%lf%lf", &x1, &yy, &r, &x2, &y2, &R); l = sqrt((x1-x2)*(x1-x2)+(yy-y2)*(yy-y2)); //cout<<l<<endl; if(R<r) { s5 = R; R = r; r = s5; } if(R >= l+r) printf("%.6f\n", r*r*PI); elseif(l >= R+r) printf("%.6f\n", 0); else{ s1 = acos((r*r+l*l-R*R)/2/r/l); s2 = acos((R*R+l*l-r*r)/2/R/l); s3 = cos(s1)*r*sin(s1)*r; s4 = cos(s2)*R*sin(s2)*R; s1 = r*r*s1; s2 = R*R*s2; printf("%f\n", s1-s3+s2-s4); } }return 0; }
UESTC1713 無關青雲路,無關詩書,無你處,無江湖