View Compilation Error

0_0_11937527_23152.cpp:13: error: expected constructor, destructor, or type conversion before '<' token
0_0_11937527_23152.cpp:13: error: expected `,' or `;' before '<' token
0_0_11937527_23152.cpp: In function `int bfs()':
0_0_11937527_23152.cpp:24: error: `Q' undeclared (first use this function)
0_0_11937527_23152.cpp:24: error: (Each undeclared identifier is reported only once for each function it appears in.)