View Compilation Error

0_0_8556430_28460.cpp:13: error: `set' does not name a type
0_0_8556430_28460.cpp: In member function `void Num::init(int)':
0_0_8556430_28460.cpp:15: error: `v' undeclared (first use this function)
0_0_8556430_28460.cpp:15: error: (Each undeclared identifier is reported only once for each function it appears in.)
0_0_8556430_28460.cpp: In member function `int Num::get()':
0_0_8556430_28460.cpp:20: error: `template<class _Key, class _Compare, class _Alloc> class std::set' used without template parameters
0_0_8556430_28460.cpp:20: error: missing template arguments before "i"
0_0_8556430_28460.cpp:20: error: expected `;' before "i"
0_0_8556430_28460.cpp:21: error: `i' undeclared (first use this function)
0_0_8556430_28460.cpp:22: error: `v' undeclared (first use this function)
0_0_8556430_28460.cpp: In member function `void Num::push(int)':
0_0_8556430_28460.cpp:26: error: `v' undeclared (first use this function)