foo.cc: In function 'int main()':
foo.cc:28:13: warning: format '%f' expects argument of type 'double', but argument 2 has type 'int' [-Wformat=]
   28 |  printf("%.2f",a);
      |          ~~~^  ~
      |             |  |
      |             |  int
      |             double
      |          %.2d

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