foo.c: In function 'main':
foo.c:14:4: warning: suggest explicit braces to avoid ambiguous 'else' [-Wdangling-else]
  if(max==a)
    ^
foo.c:19:4: warning: suggest explicit braces to avoid ambiguous 'else' [-Wdangling-else]
  if(max==b)
    ^
foo.c:24:4: warning: suggest explicit braces to avoid ambiguous 'else' [-Wdangling-else]
  if(max==c)
    ^
foo.c:7:2: 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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