Main.cc: In function 'int main()':
Main.cc:8:24: error: expression cannot be used as a function
printf("%.2f\n,"(a+b+c)/3.0);
^
Main.cc:7:28: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
scanf("%d %d %d",&a,&b,&c);
^