prepare (1/3): 
finished

make (2/3): 
g++ -g -Wall -o2 -o main.o -c main.cpp 
main.cpp: In function 'int main(int, char**)':
main.cpp:156:21: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
     if(_topo.size() == _size) {
        ~~~~~~~~~~~~~^~~~~~~~
main.cpp:199:38: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
                     for(int id = 1;id<=D.size();id++){
                                    ~~^~~~~~~~~~
main.cpp:189:11: warning: variable 'it_delete' set but not used [-Wunused-but-set-variable]
      auto it_delete = T.erase(itr_t);
           ^~~~~~~~~
main.cpp:191:13: warning: unused variable 'maxa' [-Wunused-variable]
         int maxa= MAX_INT;
             ^~~~
g++ -g -Wall -o2 -o main main.o
finished

clean (3/3): 
finished

all task finished, build successfully