foo.cc: In function ‘int main()’:
foo.cc:5:15: warning: unused variable ‘avg’ [-Wunused-variable]
    5 |     int a,b,c,avg,max;
      |               ^~~
foo.cc:5:19: warning: unused variable ‘max’ [-Wunused-variable]
    5 |     int a,b,c,avg,max;
      |                   ^~~