foo.cc: In function 'int main()':
foo.cc:8:9: error: cannot convert 'float' to 'const char*'
    8 | printf (sum);
      |         ^~~
      |         |
      |         float
In file included from foo.cc:1:
/nix/store/y8wfrgk7br5rfz4221lfb9v8w3n0cnyd-glibc-2.37-8-dev/include/stdio.h:356:43: note:   initializing argument 1 of 'int printf(const char*, ...)'
  356 | extern int printf (const char *__restrict __format, ...);
      |                    ~~~~~~~~~~~~~~~~~~~~~~~^~~~~~~~

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