foo.cc: In function 'void bfs()':
foo.cc:52:23: warning: suggest parentheses around '&&' within '||' [-Wparentheses]
   52 |    cost=(nd==dd||x==sx&&y==sy)?0:1;
      |                  ~~~~~^~~~~~~
foo.cc: In function 'int main()':
foo.cc:22:7: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   22 |  scanf("%d%d",&n,&m);
      |  ~~~~~^~~~~~~~~~~~~~
foo.cc:25:9: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   25 |    scanf("%d",&s[i][j]);
      |    ~~~~~^~~~~~~~~~~~~~~
foo.cc:26:7: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   26 |  scanf("%d%d%d%d",&sx,&sy,&bx,&by);
      |  ~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~

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