foo.cc: In function 'int main()':
foo.cc:27:6: warning: this 'for' clause does not guard... [-Wmisleading-indentation]
   27 |      for(j=1;j<=m-2;j++)
      |      ^~~
foo.cc:29:3: note: ...this statement, but the latter is misleadingly indented as if it were guarded by the 'for'
   29 |   r->next=r->next->next;
      |   ^
foo.cc:12:11: warning: unused variable 'k' [-Wunused-variable]
   12 |  long i,j,k,l;
      |           ^
foo.cc:12:13: warning: unused variable 'l' [-Wunused-variable]
   12 |  long i,j,k,l;
      |             ^

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