foo.cc: In function 'int main()':
foo.cc:5:7: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
    5 |  scanf("%d",&N);
      |  ~~~~~^~~~~~~~~
foo.cc:8:8: warning: 't' may be used uninitialized in this function [-Wmaybe-uninitialized]
    8 |  cout<<t<<endl;
      |        ^

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