Eight Queens Problem-backtracking method (MATLAB)

1. Description of the problem

The eight Queens question was introduced in 1850 by the famous mathematician Gauss in 19th century. The problem is: put 8 queens on the 8*8 board so that they cannot attack each other, that is, any two queens cannot be in the consent line, the same column, or the agreed slash.

2.matlab Code

function Placequeen (row,stack,n)% backtracking Place Queen if Row>n    Printqueen (n,stack);% print checkerboard else for    col=1:n        Stack ( Row) =col;        If row==1| | Conflict (row,col,n,stack)% detect conflict            Placequeen (row+1,stack,n);        End        Stack (row) =0;    EndEnd% Sub function: Detect conflict function result=conflict (row,col,n,stack)% detect conflict result=1;for i=1:row-1 if    stack (i) ~=0        if (( Stack (i) ==col) | | (ABS (Row-i) ==abs (Col-stack (i))) % conflict: In the same line, Slash on            result=0;            break;        End        if result==0 break            ;        End    endend%: Print checkerboard information function printqueen (n,stack) global solutionnum;% define global variables to accumulate the number of methods solutionnum=solutionnum+1 ;  Disp ([' num2str ', ' solutionnum ', ' method: ') ' for i=1:n for    j=1:n        if J==stack (i)            fprintf (' 1   ')        else            fprintf (' 0   ')        end    End    fprintf (' \ n ') end

placequeen.m

Clear ALLCLC Global solutionnum;solutionnum=0;% number of record methods n=8;% Queens number%matrix=zeros (N);% Store Queens location information stack=[0 0 0 0 0 0 0 0]; Placequeen (1,stack,n)% call placement method

queen.m

Eight Queens Problem-backtracking method (MATLAB)