foo.cc: In function 'int main()':
foo.cc:9:11: warning: format '%d' expects argument of type 'int*', but argument 2 has type 'long long int*' [-Wformat=]
    9 |   scanf("%d",&a);
      |          ~^  ~~
      |           |  |
      |           |  long long int*
      |           int*
      |          %lld
foo.cc:9:8: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
    9 |   scanf("%d",&a);
      |   ~~~~~^~~~~~~~~

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