foo.c: In function 'main':
foo.c:10:12: warning: format '%lu' expects argument of type 'long unsigned int', but argument 2 has type 'int' [-Wformat=]
  printf("%lu %lu", a, b);
          ~~^
          %u
foo.c:10:16: warning: format '%lu' expects argument of type 'long unsigned int', but argument 3 has type 'int' [-Wformat=]
  printf("%lu %lu", a, b);
              ~~^
              %u
foo.c:5:2: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
  scanf("%d", &t);
  ^~~~~~~~~~~~~~~

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