foo.cc: In function 'int main()':
foo.cc:8:9: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
    8 |    scanf("%f,%f,%c",&a,&b,&op);
      |    ~~~~~^~~~~~~~~~~~~~~~~~~~~~
foo.cc:24:11: warning: 'c' may be used uninitialized in this function [-Wmaybe-uninitialized]
   24 |     printf("%.2f",c);
      |     ~~~~~~^~~~~~~~~~

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