AtCoder Beginner Contest 168 [ C - : (Colon) ] https://atcoder.jp/contests/abc168/tasks/abc168_c

abc168_c.py

'''
[問題]
https://atcoder.jp/contests/abc168/tasks/abc168_c
'''

import sys
import math

sys.setrecursionlimit(10 ** 6)  # 再帰上限の引き上げ
input = sys.stdin.readline

INF = 2 ** 63 - 1

A, B, H, M = map(int, input().split())

# 時針の位置
h_shita = (H * 60 + M)/(12 * 60)
h_x = A * math.cos(2 * math.pi * h_shita)
h_y = A * math.sin(2 * math.pi * h_shita)

# 分針の位置
m_shita = M/60
m_x = B * math.cos(2 * math.pi * m_shita)
m_y = B * math.sin(2 * math.pi * m_shita)

# 距離の計算
ans = math.sqrt( (h_x - m_x) ** 2 + (h_y - m_y) ** 2)
print(ans)