View Compilation Error

0_0_38930562_23446.cpp: In function 'int main()':
0_0_38930562_23446.cpp:8:26: error: expected primary-expression before '|' token
    8 | while(cin>>a>>b>>c>>d,a| |b| |c| |d)
      |                          ^
0_0_38930562_23446.cpp:8:30: error: expected primary-expression before '|' token
    8 | while(cin>>a>>b>>c>>d,a| |b| |c| |d)
      |                              ^
0_0_38930562_23446.cpp:8:34: error: expected primary-expression before '|' token
    8 | while(cin>>a>>b>>c>>d,a| |b| |c| |d)
      |                                  ^