src.cpp:7:1: error: 'voi' does not name a type
voi nhap () {
^
src.cpp: In function 'void BFS(int)':
src.cpp:43:7: error: 'main' was not declared in this scope
main () {
^
src.cpp:56:1: error: expected '}' at end of input
}
^
src.cpp:56:1: error: expected '}' at end of input