foo.c: In function 'main':
foo.c:6:22: warning: suggest parentheses around '&&' within '||' [-Wparentheses]
  if (b == 1 && c > 0 && c <= 31
      ~~~~~~~~~~~~~~~~^~~~~~~~~~
foo.c:8:29: warning: suggest parentheses around '&&' within '||' [-Wparentheses]
          || b == 3 && c > 0 && c <= 31
             ~~~~~~~~~~~~~~~~^~~~~~~~~~
foo.c:9:29: warning: suggest parentheses around '&&' within '||' [-Wparentheses]
          || b == 5 && c > 0 && c <= 31
             ~~~~~~~~~~~~~~~~^~~~~~~~~~
foo.c:10:29: warning: suggest parentheses around '&&' within '||' [-Wparentheses]
          || b == 7 && c > 0 && c <= 31
             ~~~~~~~~~~~~~~~~^~~~~~~~~~
foo.c:11:29: warning: suggest parentheses around '&&' within '||' [-Wparentheses]
          || b == 8 && c > 0 && c <= 31
             ~~~~~~~~~~~~~~~~^~~~~~~~~~
foo.c:12:30: warning: suggest parentheses around '&&' within '||' [-Wparentheses]
          || b == 10 && c > 0 && c <= 31
             ~~~~~~~~~~~~~~~~~^~~~~~~~~~
foo.c:13:30: warning: suggest parentheses around '&&' within '||' [-Wparentheses]
          || b == 12 && c > 0 && c <= 31
             ~~~~~~~~~~~~~~~~~^~~~~~~~~~
foo.c:14:29: warning: suggest parentheses around '&&' within '||' [-Wparentheses]
          || b == 2 && c > 0 && c <= 29
             ~~~~~~~~~~~~~~~~^~~~~~~~~~
foo.c:15:29: warning: suggest parentheses around '&&' within '||' [-Wparentheses]
          || b == 4 && c > 0 && c <= 30
             ~~~~~~~~~~~~~~~~^~~~~~~~~~
foo.c:16:29: warning: suggest parentheses around '&&' within '||' [-Wparentheses]
          || b == 6 && c > 0 && c <= 30
             ~~~~~~~~~~~~~~~~^~~~~~~~~~
foo.c:17:29: warning: suggest parentheses around '&&' within '||' [-Wparentheses]
          || b == 9 && c > 0 && c <= 30
             ~~~~~~~~~~~~~~~~^~~~~~~~~~
foo.c:18:30: warning: suggest parentheses around '&&' within '||' [-Wparentheses]
          || b == 11 && c > 0 && c <= 30
             ~~~~~~~~~~~~~~~~~^~~~~~~~~~
foo.c:5:2: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
  scanf("%d-%d-%d", &a, &b, &c);
  ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~

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