Description

试求满足下述立方和不等式的m的最大整数解1x1x1 + 2x2x2 + 3x3x3 +......+ mxmxm <= n.

Format

Input

输入n的值，1 <= n <= 100000

Output

输出最大的m

Samples

50

3

Limitation

1s, 1024KiB for each test case.