/in/foo.cc: In function 'int main()':
/in/foo.cc:31:12: warning: 'end' may be used uninitialized in this function [-Wmaybe-uninitialized]
  int start,end;
            ^~~
/in/foo.cc:31:6: warning: 'start' may be used uninitialized in this function [-Wmaybe-uninitialized]
  int start,end;
      ^~~~~
/in/foo.cc:12:6: warning: 'start1' may be used uninitialized in this function [-Wmaybe-uninitialized]
  int start1,sum=0;
      ^~~~~~