foo.c: In function 'main':
foo.c:20:12: warning: unused variable 'm' [-Wunused-variable]
  int i,j,l,m,sx,sy;
            ^
foo.c:20:10: warning: unused variable 'l' [-Wunused-variable]
  int i,j,l,m,sx,sy;
          ^
foo.c:21:2: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
  scanf("%d",&n);
  ^~~~~~~~~~~~~~
foo.c:25:4: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
    scanf("%c",&A[i][j]);
    ^~~~~~~~~~~~~~~~~~~~
foo.c:34:2: warning: 'sy' may be used uninitialized in this function [-Wmaybe-uninitialized]
  dfs(sx,sy,0);
  ^~~~~~~~~~~~
foo.c:34:2: warning: 'sx' may be used uninitialized in this function [-Wmaybe-uninitialized]

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