prepare (1/3): 
finished

make (2/3): 
g++ -g -Wall -O2 -o p2.o -c p2.cpp 
p2.cpp: In function 'int main()':
p2.cpp:31:52: warning: 'target' may be used uninitialized in this function [-Wmaybe-uninitialized]
     cout << "The order-" << rank << " item is " << target << endl;
                                                    ^~~~~~
g++ -g -Wall -O2 -o selection.o -c selection.cpp 
selection.cpp: In function 'int Dselect(int*, int, int)':
selection.cpp:63:9: warning: 'pivot' is used uninitialized in this function [-Wuninitialized]
     int pivot;
         ^~~~~
g++ -g -Wall -O2 -o main p2.o selection.o
finished

clean (3/3): 
finished

all task finished, build successfully