foo.cc:8:6: error: conversion from 'double' to 'long unsigned int' in a converted constant expression
    8 | ll f[1e7];
      |      ^~~
foo.cc:8:6: error: could not convert '1.0e+7' from 'double' to 'long unsigned int'
foo.cc:8:6: error: size of array 'f' has non-integral type 'double'
foo.cc: In function 'void cx()':
foo.cc:21:7: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   21 |  scanf("%lld", &n);
      |  ~~~~~^~~~~~~~~~~~
foo.cc: In function 'int main()':
foo.cc:25:7: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   25 |  scanf("%lld", &T);
      |  ~~~~~^~~~~~~~~~~~

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