台球碰撞 （C++代码）

#include<cstdio>
#include<iostream>
#include<cmath>
using namespace std;
int main(void)
{
    int L_box[30],W_box[30],x_box[30],y_box[30];
    int R_box[30],a_box[30],v_box[30],s_box[30];
    int i=0,n;
    do{
        scanf("%d%d%d%d%d%d%d%d",L_box+i,W_box+i,x_box+i,y_box+i,R_box+i,a_box+i,v_box+i,s_box+i);
        if(L_box[i]==0) break;
        i=i+1;
        }while(1);
     n=i;
     for(i=0;i<n;i++)
     {
             double x=(double)x_box[i],y=(double)y_box[i],v=(double)v_box[i],s=(double)s_box[i],L=(double)L_box[i],W=(double)W_box[i],R=(double)R_box[i];
             double angle=1.0*a_box[i]*acos(-1)/180;
             double dx=v*s*cos(angle),dy=v*s*sin(angle);
             x=x+dx;
             y=y+dy;
             while(x>L-R || x<R || y>W-R || y<R )
             {
                 if(x>L-R)      x=2*(L-R)-x;
                 if(y>W-R)    y=2*(W-R)-y;
                 if(x<R)         x=2*R-x;
                 if(y<R)         y=2*R-y;
             }
             if(i<n-1)
            printf("%.2lf %.2lf\n",x,y);
            else printf("%.2lf %.2lf",x,y);
     }
    return 0;
}

有误差，满足给出数据，但是对于大数据有误差，答案错误
#include<cstdio>
#include<iostream>
#include<cmath>
using namespace std;
int main(void)
{
    int L_box[30],W_box[30],x_box[30],y_box[30];
    int R_box[30],a_box[30],v_box[30],s_box[30];
    int i=0,n;
    do{
        scanf("%d%d%d%d%d%d%d%d",L_box+i,W_box+i,x_box+i,y_box+i,R_box+i,a_box+i,v_box+i,s_box+i);
        if(L_box[i]==0) break;
        i=i+1;
        }while(1);
     n=i;
     for(i=0;i<n;i++)
     {
             int s=s_box[i];
             double x=(double)x_box[i],y=(double)y_box[i],v=(double)v_box[i],L=(double)L_box[i],W=(double)W_box[i],R=(double)R_box[i];
             double angle=1.0*a_box[i]*acos(-1)/180;
             double dx=v*cos(angle),dy=v*sin(angle);
              for(int j=1;j<=s;j++)
              {
                 x+=dx,y+=dy;
                 if(x>L-R)      x=2*(L-R )-x,dx=-dx;
                 if(y>W-R)    y=2*(W-R)-y,dy=-dy;
                 if(x<R)         x=2*R-x,dx=-dx;
                 if(y<R)         y=2*R-y,dy=-dy;
              }
             if(i<n-1)
            printf("%.2lf %.2lf\n",x,y);
            else printf("%.2lf %.2lf",x,y);
     }
    return 0;
}