View Compilation Error

0_0_30520290_14367.cpp: In function 'int main()':
0_0_30520290_14367.cpp:5:5: error: 'a' was not declared in this scope
 {   a xor c & b xor c
     ^
0_0_30520290_14367.cpp:5:11: error: 'c' was not declared in this scope
 {   a xor c & b xor c
           ^
0_0_30520290_14367.cpp:5:15: error: 'b' was not declared in this scope
 {   a xor c & b xor c
               ^