View Compilation Error

0_0_31195593_25579.cpp: In function 'int main()':
0_0_31195593_25579.cpp:8:10: error: 'a' was not declared in this scope
       if(a==o&&b==0)
          ^
0_0_31195593_25579.cpp:8:13: error: 'o' was not declared in this scope
       if(a==o&&b==0)
             ^
0_0_31195593_25579.cpp:8:16: error: 'b' was not declared in this scope
       if(a==o&&b==0)
                ^