t | from decimal import * | t | from decimal import * |
| | | |
| def pi(): | | def pi(): |
| three = Decimal(3) | | three = Decimal(3) |
| lasts, t, s, n, na, d, da = (0, three, 3, 1, 0, 0, 24) | | lasts, t, s, n, na, d, da = (0, three, 3, 1, 0, 0, 24) |
| while s != lasts: | | while s != lasts: |
| lasts = s | | lasts = s |
| n, na = (n + na, na + 8) | | n, na = (n + na, na + 8) |
| d, da = (d + da, da + 32) | | d, da = (d + da, da + 32) |
| t = t * n / d | | t = t * n / d |
| s += t | | s += t |
| return s | | return s |
| | | |
| def cos(x): | | def cos(x): |
| i, lasts, s, fact, num, sign = (0, 0, 1, 1, 1, 1) | | i, lasts, s, fact, num, sign = (0, 0, 1, 1, 1, 1) |
| while s != lasts: | | while s != lasts: |
| lasts = s | | lasts = s |
| i += 2 | | i += 2 |
| fact *= i * (i - 1) | | fact *= i * (i - 1) |
| num *= x * x | | num *= x * x |
| sign *= -1 | | sign *= -1 |
| s += num / fact * sign | | s += num / fact * sign |
| return s | | return s |
| | | |
| def sin(x): | | def sin(x): |
| i, lasts, s, fact, num, sign = (1, 0, x, 1, x, 1) | | i, lasts, s, fact, num, sign = (1, 0, x, 1, x, 1) |
| while s != lasts: | | while s != lasts: |
| lasts = s | | lasts = s |
| i += 2 | | i += 2 |
| fact *= i * (i - 1) | | fact *= i * (i - 1) |
| num *= x * x | | num *= x * x |
| sign *= -1 | | sign *= -1 |
| s += num / fact * sign | | s += num / fact * sign |
| return s | | return s |
| A, E = (Decimal(input()), int(input())) | | A, E = (Decimal(input()), int(input())) |
| getcontext().prec = E + 5 | | getcontext().prec = E + 5 |
| r = A * pi() / Decimal(200) | | r = A * pi() / Decimal(200) |
| r = sin(r) / cos(r) | | r = sin(r) / cos(r) |
| getcontext().prec = E | | getcontext().prec = E |
| print(+r) | | print(+r) |