foo.c: In function 'check':
foo.c:14:27: warning: unused variable 'j' [-Wunused-variable]
   14 |         int dx=0,dy=0,i=0,j=0;
      |                           ^
foo.c:14:23: warning: unused variable 'i' [-Wunused-variable]
   14 |         int dx=0,dy=0,i=0,j=0;
      |                       ^
foo.c:14:18: warning: unused variable 'dy' [-Wunused-variable]
   14 |         int dx=0,dy=0,i=0,j=0;
      |                  ^~
foo.c:14:13: warning: unused variable 'dx' [-Wunused-variable]
   14 |         int dx=0,dy=0,i=0,j=0;
      |             ^~

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