foo.cc: In function 'int main()':
foo.cc:64:43: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   64 |         for(int i = 2; i <= 9; i ++) scanf("%d", &ch[i]);
      |                                      ~~~~~^~~~~~~~~~~~~~
foo.cc: In function 'void bfs()':
foo.cc:20:12: warning: 'a1[1]' may be used uninitialized in this function [-Wmaybe-uninitialized]
   20 |     if(a1[1]+a1[5]+a1[9] != 15) return false;
      |        ~~~~^
foo.cc:20:18: warning: 'a1[5]' may be used uninitialized in this function [-Wmaybe-uninitialized]
   20 |     if(a1[1]+a1[5]+a1[9] != 15) return false;
      |              ~~~~^
foo.cc:20:24: warning: 'a1[9]' may be used uninitialized in this function [-Wmaybe-uninitialized]
   20 |     if(a1[1]+a1[5]+a1[9] != 15) return false;
      |                    ~~~~^
foo.cc:21:12: warning: 'a1[7]' may be used uninitialized in this function [-Wmaybe-uninitialized]
   21 |     if(a1[7]+a1[8]+a1[9] != 15) return false;
      |        ~~~~^
foo.cc:21:18: warning: 'a1[8]' may be used uninitialized in this function [-Wmaybe-uninitialized]
   21 |     if(a1[7]+a1[8]+a1[9] != 15) return false;
      |              ~~~~^

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