View Compilation Error

0_0_38463623_16550.cpp: In function 'int main()':
0_0_38463623_16550.cpp:13:12: error: 'a' was not declared in this scope
     cin >> a >> b;
            ^
0_0_38463623_16550.cpp:13:17: error: 'b' was not declared in this scope
     cin >> a >> b;
                 ^