foo.cc: In function 'int main()':
foo.cc:48:15: warning: unused variable 'start' [-Wunused-variable]
   48 |  int i,n,a[N],start,end;
      |               ^~~~~
foo.cc:48:21: warning: unused variable 'end' [-Wunused-variable]
   48 |  int i,n,a[N],start,end;
      |                     ^~~
foo.cc: In function 'void quickSort(int*, int, int)':
foo.cc:41:16: warning: 'pos' may be used uninitialized in this function [-Wmaybe-uninitialized]
   41 |   pos = segment(a,start,pos - 1);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~
foo.cc: In function 'int main()':
foo.cc:41:16: warning: 'pos' may be used uninitialized in this function [-Wmaybe-uninitialized]
   41 |   pos = segment(a,start,pos - 1);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~
foo.cc:38:6: note: 'pos' was declared here
   38 |  int pos;
      |      ^~~

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