/*
 * @(#) smt2_1.c - Program for determining target points hit extrapolated
 * trajectory capture gate (Task 2_1 at the Special Military Training course).
 * (c) 1997 Ivan Maidanski <ivmai@chat.ru> http://ivmai.chat.ru
 * Freeware program source. All rights reserved.
 **
 * Language: ANSI C
 * Tested with: Borland C++ v3.1
 * Last modified: 1997-05-05 21:15:00 GMT+04:00
 */

#include <stdio.h>

#define MAX_M 20

float ax[MAX_M],ay[MAX_M],az[MAX_M];

float extrapolate(float dt, float x, float dx, float ddx)
{
 return (x+dt*(dx+dt*ddx/2.0));
}

int ingate(float dx, float dy, float dz,
           float sigmax, float sigmay, float sigmaz)
{
 return ((dx/sigmax)*(dx/sigmax)+(dy/sigmay)*(dy/sigmay)+
         (dz/sigmaz)*(dz/sigmaz)<9.0);
}

int main()
{
 int i,m;
 float tk,tn;
 float x,dx,ddx,y,dy,ddy,z,dz,ddz;
 float sigmax,sigmay,sigmaz;
 printf("tk= ");
 scanf("%f",&tk);
 printf("x= ");
 scanf("%f",&x);
 printf("x'= ");
 scanf("%f",&dx);
 printf("x''= ");
 scanf("%f",&ddx);
 printf("y= ");
 scanf("%f",&y);
 printf("y'= ");
 scanf("%f",&dy);
 printf("y''= ");
 scanf("%f",&ddy);
 printf("z= ");
 scanf("%f",&z);
 printf("z'= ");
 scanf("%f",&dz);
 printf("z''= ");
 scanf("%f",&ddz);
 printf("sigma_x= ");
 scanf("%f",&sigmax);
 printf("sigma_y= ");
 scanf("%f",&sigmay);
 printf("sigma_z= ");
 scanf("%f",&sigmaz);
 printf("\n");
 printf("m= ");
 scanf("%d",&m);
 printf("tn= ");
 scanf("%f",&tn);
 for (i=0;i<m;i++)
 {
  printf("x%d= ",i+1);
  scanf("%f",&ax[i]);
  printf("y%d= ",i+1);
  scanf("%f",&ay[i]);
  printf("z%d= ",i+1);
  scanf("%f",&az[i]);
 }
 printf("\n");
 tn-=tk;
 x=extrapolate(tn,x,dx,ddx);
 y=extrapolate(tn,y,dy,ddy);
 z=extrapolate(tn,z,dz,ddz);
 for (i=0;i<m;i++)
 {
  printf("%d. ",i+1);
  if (ingate(ax[i]-x,ay[i]-y,az[i]-z,sigmax,sigmay,sigmaz))
    printf("%f,%f,%f",ax[i],ay[i],az[i]);
    else printf("Target not identified.");
  printf("\n");
 }
 printf("\n");
 return 0;
}