/in/foo.cc: In function 'int main()':
/in/foo.cc:13:17: error: expected '(' before '{' token
   13 |                 {
      |                 ^
      |                 (
/in/foo.cc:13:17: error: expected primary-expression before '{' token
/in/foo.cc:12:22: error: expected ')' before '{' token
   12 |                 while
      |                      ^
      |                      )
   13 |                 {
      |                 ~     
/in/foo.cc:5:15: warning: unused variable 'sum' [-Wunused-variable]
    5 |         int n,sum;
      |               ^~~