Recursion-down stairs

Total time limit: 1000ms memory limit: 1000kB

Describe

from upstairs to downstairs a total of h steps, each step there are 3 ways to go: Walk 1 steps, walk 2 steps, walk 3 steps. Q. How many options can you get out of and print out a specific plan?

Input

number of steps H

Output

various ways to go and the total number of solutions

Sample input

5

Sample output

Plan 1:32

Plan 2:311

Plan 3:23

Plan 4:221

Plan 5:212

Plan 6:2,111

Plan 7:131

Plan 8:122

Plan 9:1211

Plan 10:113

Plan 11:1121

Plan 12:1112

Plan 13:11,111

Number of Plans:13

Thought: Because every step of the way is slightly the same, you can use a recursive method.

Code:

1#include <iostream>2 using namespacestd;3 4 inttake[ About];5 intnum =0;//Number of programmes6 voidTry (intIints)7 {8      for(intj=3; J>0; j--)9     {Ten         if(i>=j) One         { ATake[s] =J; -             if(i==j) -             { thenum++; -cout<<"Plan"<<num<<":"; -                 //output sub-scheme -                  for(intk=1; k<=s; k++) +cout<<Take[k]; -cout<<Endl; +             } A             Else //not yet to go downstairs atTry (I-j, s+1); -         } -  -     } - } -  in intMain () - { to     intN; +Cin>>N; -  theTry (N,1); *  $cout<<"Number of plans:"<<num<<Endl;Panax Notoginseng     return 0; -}

Recursion-down stairs