/in/foo.cc: In function 'void search(int)':
/in/foo.cc:18:20: warning: unused variable 'key' [-Wunused-variable]
  int size,want,now,key=0;
                    ^~~
/in/foo.cc: In function 'int main()':
/in/foo.cc:50:12: warning: unused variable 'c' [-Wunused-variable]
  int i,a,b,c;
            ^