Staircase.cpp

// Staircase.cpp : This file contains the 'main' function. Program execution begins and ends there.
//

#include <iostream>
using namespace std;

int way = 0; // counter of total ways
int x[] = { 1,2,3 };  //the set of your move choice
void climb(int N) {
    if (N == 0) {
        way++;
    }
    else {
        for (int i = 0; i < 3 && x[i]<=N; i++) {
            climb(N - x[i]);
        }
    }
}

int main()
{
   int N = 4; //total number of staircases
  
   climb(N);
   cout << way;
}

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