#include <stdio.h>
#include <stdlib.h>
#include <math.h>

int main()
{
  int c=0;
  double a,s,d;

  printf("Target at 500m\n");
  while(1){
    c=c+1;
    printf("Input Angle(0 - Pi/2):");
    scanf("%lf",&a);
    printf("Input Speed(m/s):");
    scanf("%lf",&s);
    d = (s * s * sin( 2 * a ))/9.8 ;
    printf("Distance = %lf m\n",d);

    if(d > 490 && d < 510) break;
  }

  printf("%d turns to hit\n",c);

}