[BOJ] 2193번 : 이친수

1. problem : 

https://www.acmicpc.net/problem/2193

 

 

2. solution 1 :

#include <bits/stdc++.h>
using namespace std;
int n;
long long d[95]; 
int main(void) {
	ios::sync_with_stdio(0);
	cin.tie(0);
	cin >> n;
	d[1] = 1, d[2] = 1;
	for (int i = 3; i <= n; i++) d[i] = d[i - 1] + d[i - 2];
	cout << d[n] << '\n';
}

 

3. solution 2 :

// Authored by : Hot6Mania
// Co-authored by : -
// http://boj.kr/62b94c1ad9254f87a1f6e37323f2c5bf
#include <bits/stdc++.h>
using namespace std;

typedef long long ll;

int n;
ll d[100][2];

int main(void){
  ios::sync_with_stdio(0);
  cin.tie(0);
  
  cin >> n;
  d[1][1] = 1LL;
  for(int i = 2; i <= n; ++i){
    d[i][0] = d[i-1][0] + d[i-1][1];
    d[i][1] = d[i-1][0];
  }
  cout << d[n][0] + d[n][1];
}

source code 출처 : https://github.com/encrypted-def/basic-algo-lecture/blob/master/0x10/solutions/2193.cpp

basic-algo-lecture/0x10/solutions/2193.cpp at master · encrypted-def/basic-algo-lecture