foo.c: In function 'main':
foo.c:5:13: warning: format '%c' expects argument of type 'char *', but argument 3 has type 'int *' [-Wformat=]
  scanf("%d %c %d\n%d", &a, &b, &c, &z);
            ~^              ~~
            %lc
foo.c:5:2: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
  scanf("%d %c %d\n%d", &a, &b, &c, &z);
  ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

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