foo.c: In function 'main':
foo.c:6:15: warning: missing terminating " character
    6 |         scanf("%d %d,&a,&b);
      |               ^
foo.c:6:15: error: missing terminating " character
    6 |         scanf("%d %d,&a,&b);
      |               ^~~~~~~~~~~~~~
foo.c:7:16: warning: missing terminating " character
    7 |         printf("%d,a+b);
      |                ^
foo.c:7:16: error: missing terminating " character
    7 |         printf("%d,a+b);
      |                ^~~~~~~~~
foo.c:8:20: error: expected expression before 'return'
    8 |                    return 0;
      |                    ^~~~~~
foo.c:8:29: error: expected ')' before '}' token
    8 |                    return 0;
      |                             ^
      |                             )
    9 | }
      | ~                            
foo.c:6:14: note: to match this '('
    6 |         scanf("%d %d,&a,&b);
      |              ^
foo.c:8:29: error: expected ';' before '}' token
    8 |                    return 0;
      |                             ^
      |                             ;
    9 | }
      | ~                            
foo.c:5:11: warning: unused variable 'b' [-Wunused-variable]
    5 |     int a,b;
      |           ^
foo.c:5:9: warning: unused variable 'a' [-Wunused-variable]
    5 |     int a,b;
      |         ^

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