Use the Backtracking Method to find out the full arrangement of the number of R in N Natural Numbers

The backtracking method is also called the testing method.ProblemThe limitation of the size of the problem, and the solution of the problem is enumerated and tested one by one in a certain order. In the Backtracking Method, the process of dropping the current half solution is called backtracking.
This example uses the Backtracking Method to output n natural numbers in a full arrangement of the numbers of R.CodeAs follows:

 1   Public   Void Arrange ( Int N, Int R)
 2       Int I = 0 , J;
 3       String S;
4       Int [] A = New   Int [N];
 5 A = 1 ;
 6       While ( True )
 7 {
 8           If (A-I) <= (n-R + 1 ))
9 {
 10               If (I = (R- 1 ))
 11 {
 12 S = "" ;
 13                   For (J = 0 ; J <r; j ++)
 14 {
 15 S = S + convert. tostring (A [J]) + "  ,  " ;
 16 }
 17                   //  Memo1.lines. append (TRIM (s ));  
  18 Console. writeline (s );
 19 A = a + 1 ;
 20                  Continue ;
 21 }
 22 I = I + 1 ;
 23 A = A [I- 1 ] + 1 ;
 24 }
 25           Else  
 26 {
 27              If (I = 0 )
 28 {
 29                   Break ;
 30 }
 31 I = I- 1 ;
 32 A = a + 1 ;
 33 }
34 }