求立方根
求解立方根
http://www.nowcoder.com/questionTerminal/caf35ae421194a1090c22fe223357dca
import sys num = float(sys.stdin.readline().strip()) start = 0 end = num mid = (end+start)/2 while abs(mid**3-num) > 0.001: if mid**3 > num: end = mid mid = (end+start)/2 else: start = mid mid = (end+start)/2 print(round(mid, ndigits=1))