View Compilation Error

0_0_21798418_32562.cpp: In function 'int main()':
0_0_21798418_32562.cpp:19:20: error: 'c1' was not declared in this scope
             cin >> c1 >> c2;
                    ^
0_0_21798418_32562.cpp:19:26: error: 'c2' was not declared in this scope
             cin >> c1 >> c2;
                          ^