test.cpp: In function `int main()': test.cpp:8: `a' undeclared (first use this function) test.cpp:8: (Each undeclared identifier is reported only once for each function it appears in.) test.cpp:8: `v' undeclared (first use this function) test.cpp:9: `df' undeclared (first use this function) test.cpp:10: `fd' undeclared (first use this function) test.cpp:11: parse error before `[' token