View Compilation Error

354809_0_1054.cpp:6:20: hash_set: No such file or directory
354809_0_1054.cpp: In function `int main()':
354809_0_1054.cpp:79: error: `hash_set' undeclared (first use this function)
354809_0_1054.cpp:79: error: (Each undeclared identifier is reported only once for each function it appears in.)
354809_0_1054.cpp:79: error: expected primary-expression before '>' token
354809_0_1054.cpp:79: error: `visited' undeclared (first use this function)