foo.cc: In function 'int main()':
foo.cc:7:10: warning: left operand of comma operator has no effect [-Wunused-value]
    7 |  if(-1000<a,b,c<10000)
      |     ~~~~~^~
foo.cc:7:17: warning: right operand of comma operator has no effect [-Wunused-value]
    7 |  if(-1000<a,b,c<10000)
      |                 ^~~~~
foo.cc:8:15: error: expected ';' before 'return'
    8 |  cout<<(a+b)*c
      |               ^
      |               ;
    9 |  return 0;
      |  ~~~~~~        

[Hydro](https://hydro.ac)提供评测服务