date.h:3:  Do not leave a blank line after "public:"  [whitespace/blank_line] [3]
date.h:5:  You don't need a ; after a }  [readability/braces] [4]
date.h:11:  Else clause should never be on same line as else (use 2 lines)  [whitespace/newline] [4]
date.h:18:  If an else has a brace on one side, it should have it on both  [readability/braces] [5]
date.h:18:  Else clause should never be on same line as else (use 2 lines)  [whitespace/newline] [4]
date.h:24:  If an else has a brace on one side, it should have it on both  [readability/braces] [5]
date.h:24:  Else clause should never be on same line as else (use 2 lines)  [whitespace/newline] [4]
date.h:43:  Lines should be <= 80 characters long  [whitespace/line_length] [2]
date.h:57:  Redundant blank line at the start of a code block should be deleted.  [whitespace/blank_line] [2]
date.h:31:  Add #include <string> for string  [build/include_what_you_use] [4]
date.h:74:  Could not find a newline character at the end of the file.  [whitespace/ending_newline] [5]
Done processing date.h
Total errors found: 11