Number place puzzles having triads and use as intermediates to make number place puzzles having nonets

Abstract

Methods and computer software are provided for making number place puzzles having nonets or number place puzzles having triads. For number place puzzles having triads, no object appears more than once in each row and in each column, and each triad contains no more than one object from each of three distinct groups of objects. The software comprises instructions within each of multiple nested loops that limit access to embedded loops until all selected objects form a valid solution. Multiple solutions provide information for modifying the pre-assigned objects to obtain a single solution.

1 . A computer readable medium having instructions for making a number place puzzle, comprising:
 one or more instructions for sequencing of lines of a partial or complete number place puzzle having triads;   one or more instructions for printing a finding of one complete solution or more than one complete solution for the number place puzzle having triads; and   a plurality of instructions at a plurality of locations for limiting access to the one or more instructions for printing until all assigned values form a valid solution to the number place puzzle having triads.   
     
     
         2 . The computer readable medium of  claim 1 , further comprising one or more instructions for converting the partial or complete number place puzzle having nonets to the partial or complete number place puzzle having triads. 
     
     
         3 . The computer readable medium of  claim 2 , further comprising instructions for printing one or more complete solutions for the number place puzzle having triads or one or more complete solutions for the number place puzzle having nonets. 
     
     
         4 . The computer readable medium of  claim 3 , further comprising instructions for converting the one or more complete solutions for the number place puzzle having triads to the one or more complete solutions for the number place puzzle having nonets. 
     
     
         5 . The computer readable medium of  claim 4 , wherein the plurality of instructions at a plurality of locations for limiting access comprise one or more instructions for bypassing embedded loops. 
     
     
         6 . The computer readable medium of  claim 5 , wherein the one or more instructions for bypassing the embedded loops do not process objects that are selected in embedded loops. 
     
     
         7 . The computer readable medium of  claim 6 , wherein no object appears more than once in each row and in each column, and each triad contains no more than one object from each of three distinct groups of objects. 
     
     
         8 . The computer readable medium of  claim 7 , wherein the three distinct groups of objects are numerals  1 - 3 , numerals  4 - 6 , and numerals  7 - 9 . 
     
     
         9 . A method for making a number place puzzle, comprising:
 determining multiple solutions for pre-assigned objects using the computer readable medium of  claim 1 ; and   using the multiple solutions to modify the pre-assigned objects to obtain number place puzzle having a single solution.   
     
     
         10 . A number place puzzle, comprising:
 nine columns and nine rows defining eighty-one boxes, wherein each row or each column is divided into three triads; and   sufficient pre-assigned objects to form a single solution provided that no object appears more than once in each row and each column, and that each triad contains no more than one object from each of three distinct groups of objects.   
     
     
         11 . The number place puzzle of  claim 10 , wherein the three distinct groups of objects are numerals  1 - 3 , numerals  4 - 6 , and numerals  7 - 9 .