foo.cc: In function 'int32_t calc(int)':
foo.cc:6:21: error: cannot convert '<brace-enclosed initializer list>' to 'int32_t' {aka 'int'} in return
    6 |   return {2, 1, 1, 0};
      |                     ^
foo.cc: In function 'int main()':
foo.cc:32:8: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   32 |   scanf("%d", &n);
      |   ~~~~~^~~~~~~~~~

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