/in/foo.cc: In function 'int main()':
/in/foo.cc:8:1: error: 's' was not declared in this scope
    8 | s = a + b;
      | ^
/in/foo.cc:11:1: error: 'c' was not declared in this scope
   11 | c = a + b;
      | ^
/in/foo.cc:6:13: warning: unused variable 'c\U0000ff0cs' [-Wunused-variable]
    6 | int a,b,n,m,c，s;
      |             ^~~~