题号：NC54559
时间限制：C/C++/Rust/Pascal 1秒，其他语言2秒
空间限制：C/C++/Rust/Pascal 256 M，其他语言512 M
64bit IO Format: %lld
时间限制：C/C++/Rust/Pascal 1秒，其他语言2秒
空间限制：C/C++/Rust/Pascal 256 M，其他语言512 M
64bit IO Format: %lld
题目描述
You are given two positive integers l and r,you shoud answer l⊕(l+1)⊕⋯⊕r,where ⊕ denotes the bitwise XOR operation. In XOR operation we perform the comparison of two bits, being 1 if the two bits are different, and 0 if they are the same. For example:
输入描述:
The input contain two integers l ,r (1 ≤ l ≤ r ≤1018)
输出描述:
The only output line should contain a single integer