foo.cc: In function 'int main()':
foo.cc:7:7: error: expected primary-expression before '>' token
    7 |  cin>>>a>>b>>c;
      |       ^
foo.cc:8:28: error: expected ';' before 'return'
    8 |  printf("%.1f",(a+b+c)/3.0)
      |                            ^
      |                            ;
    9 |     return 0;
      |     ~~~~~~                  
foo.cc:6:9: warning: unused variable 'avg' [-Wunused-variable]
    6 |  double avg;
      |         ^~~

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