foo.cc: In function 'int main()':
foo.cc:23:2: warning: this 'if' clause does not guard... [-Wmisleading-indentation]
   23 |  if(a[1]=='-') f1=-1,st1++,len1--;if(b[1]=='-') f2=-1,st2++,len2--;
      |  ^~
foo.cc:23:35: note: ...this statement, but the latter is misleadingly indented as if it were guarded by the 'if'
   23 |  if(a[1]=='-') f1=-1,st1++,len1--;if(b[1]=='-') f2=-1,st2++,len2--;
      |                                   ^~
foo.cc:22:7: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   22 |  scanf("%s %s",a+1,b+1);len1=strlen(a+1);len2=strlen(b+1);
      |  ~~~~~^~~~~~~~~~~~~~~~~

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