foo.cc: In function 'int main()':
foo.cc:15:8: warning: too many arguments for format [-Wformat-extra-args]
   15 |  scanf("%d",&n,&m);
      |        ^~~~
foo.cc:15:7: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   15 |  scanf("%d",&n,&m);
      |  ~~~~~^~~~~~~~~~~~

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