var navform1=""
var navform2=""
navform1 =  "<form NAME='navigation_buttons'>"
navform1 += "  <p><input LANGUAGE='JavaScript' TYPE='button' VALUE='Problem' "
navform1 += "  ONCLICK='location.href = problem' NAME='problem_button' style='beige_color'> <input "
navform1 += "  LANGUAGE='JavaScript' TYPE='button' VALUE='Hint 1' ONCLICK='location.href = hint1' "
navform1 += "  NAME='hint1_button'> <input LANGUAGE='JavaScript' TYPE='button' VALUE='Hint 2' "
navform1 += "  ONCLICK='location.href = hint2' NAME='hint2_button'> <input LANGUAGE='JavaScript' "
navform1 += "  TYPE='button' VALUE='Solution' ONCLICK='location.href = solution' NAME='solution_button'> <input "
navform1 += "  LANGUAGE='JavaScript' TYPE='button' VALUE='Chapter "
navform2 = "'  ONCLICK='location.href = chapter_index' NAME='chapter_button'> <input "
navform2 += "  LANGUAGE='JavaScript' TYPE='button' VALUE='Index to chapters' "
navform2 += "  ONCLICK='location.href = index' NAME='index_button'> </p> "
navform2 += "</form>"