View Compilation Error

0_0_9345290_25897.cpp: In function `long long int cal(long long int)':
0_0_9345290_25897.cpp:21: error: `B' undeclared (first use this function)
0_0_9345290_25897.cpp:21: error: (Each undeclared identifier is reported only once for each function it appears in.)
0_0_9345290_25897.cpp:22: error: `A' undeclared (first use this function)
0_0_9345290_25897.cpp:23: error: `C' undeclared (first use this function)
0_0_9345290_25897.cpp: In function `int main()':
0_0_9345290_25897.cpp:46: error: `get' undeclared (first use this function)