#P784E. Twisted Circuit

    ID: 5615 远端评测题 2000ms 64MiB 尝试: 0 已通过: 0 难度: 7 上传者: 标签>*special problembrute forceimplementation*2000

Twisted Circuit

Description

The input consists of four lines, each line containing a single digit 0 or 1.

Output a single digit, 0 or 1.

Input

The input consists of four lines, each line containing a single digit 0 or 1.

Output

Output a single digit, 0 or 1.

0
1
1
0

0