foo.cc: In function 'int main()':
foo.cc:12:29: warning: suggest parentheses around '&&' within '||' [-Wparentheses]
   if(f=='-'&&af>be&&(be>='0'&&af<='9'||be>='a'&&af<='z')){
                      ~~~~~~~^~~~~~~~~
foo.cc:7:7: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
  scanf("%d%d%d%s",&p1,&p2,&p3,ch);
  ~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~

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