foo.cc: In function 'int main()':
foo.cc:30:7: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   30 |  scanf("%d%d",&M,&N);
      |  ~~~~~^~~~~~~~~~~~~~
foo.cc:34:8: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   34 |   scanf("%lld",&a[i][j]);
      |   ~~~~~^~~~~~~~~~~~~~~~~
foo.cc:70:7: warning: 'x' may be used uninitialized in this function [-Wmaybe-uninitialized]
   70 |  print(M,x);
      |  ~~~~~^~~~~

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