View Compilation Error

0_0_8942363_14844.cpp: In function `int main()':
0_0_8942363_14844.cpp:17: error: `C' undeclared (first use this function)
0_0_8942363_14844.cpp:17: error: (Each undeclared identifier is reported only once for each function it appears in.)
0_0_8942363_14844.cpp:20: error: `n' undeclared (first use this function)