foo.cc: In function 'int main()':
foo.cc:8:27: warning: format '%f' expects argument of type 'float*', but argument 2 has type 'double*' [-Wformat=]
  scanf("%f,%f,%c",&a,&b,&c);
                   ~~      ^
foo.cc:8:27: warning: format '%f' expects argument of type 'float*', but argument 3 has type 'double*' [-Wformat=]
foo.cc:8:7: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
  scanf("%f,%f,%c",&a,&b,&c);
  ~~~~~^~~~~~~~~~~~~~~~~~~~~

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