hdu 1724

Ellipse

不能用float

#include<stdio.h>#include<math.h>#include<stdlib.h>int main(){ int a,b,i,j,n,s,t; double re,ans,ant; scanf("%d",&n); while(n--) { scanf("%d%d%d%d",&a,&b,&s,&t); ant=acos(t/(float)a); ans=acos(s/(float)a); re=a*b*((sin(2*ant)-sin(2*ans))/2-(ant-ans)); printf("%.3f/n",re); } //system("pause"); }