View Compilation Error

0_0_11652333_13597.cpp: In function `int main()':
0_0_11652333_13597.cpp:51: error: `cal' undeclared (first use this function)
0_0_11652333_13597.cpp:51: error: (Each undeclared identifier is reported only once for each function it appears in.)
0_0_11652333_13597.cpp:52: error: `cal2' undeclared (first use this function)