foo.c: In function 'main':
foo.c:7:20: error: expected ')' before 'a'
    7 |     printf("%lld\n"a + b);
      |                    ^
      |                    )
foo.c:7:16: warning: format '%lld' expects a matching 'long long int' argument [-Wformat=]
    7 |     printf("%lld\n"a + b);
      |             ~~~^
      |                |
      |                long long int
foo.c:6:2: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
    6 |  scanf("%lld %lld", &a, &b);
      |  ^~~~~~~~~~~~~~~~~~~~~~~~~~

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