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

#define MAXN 16384  // musí být mocninou dvojky	
#define MAX (2*MAXN+1)

static struct seg {
  double x, y;
  int a;
} seg[MAX];

static void merge(int i)
{
  struct seg *l = seg+2*i, *r = l+1;
  double a = 2*M_PI*l->a/360;
  seg[i].x = l->x + r->x*cos(a) - r->y*sin(a);
  seg[i].y = l->y + r->x*sin(a) + r->y*cos(a);
  seg[i].a = (l->a + r->a) % 360;
}

int main(void)
{
  int i, j, k, n0, N;

  scanf("%d", &n0);
  for (N=1; N<n0; N*=2);
  for (i=0; i<n0; i++)
    scanf("%lf", &seg[N+i].y);
  for (i=N-1; i>=1; i--)
    merge(i);
  while (scanf("%d%d", &j, &k) == 2)
    {
      j = N+j-1;
      seg[j].a = (180+k) % 360;
      while (j != 1)
	merge(j /= 2);
      printf("%.2f %.2f\n", seg[1].x, seg[1].y);
    }
  return 0;
}