View Compilation Error

0_0_16621176_8305.cpp: In function 'int gcd(int, int)':
0_0_16621176_8305.cpp:20:21: error: 'g' was not declared in this scope
     return !b ? a : g
                     ^
0_0_16621176_8305.cpp:20:21: error: expected ';' at end of input
0_0_16621176_8305.cpp:20:21: error: expected '}' at end of input