poj2663,dynamic programming

poj_2663_AC.cpp

 /*
** id :template
** author : swap_coder
** time:
*/


#include<vector>
#include<algorithm>
#include<cstdio>
#include<cstring>
#include<cmath>
#include <iostream>
#include <map>
#include <queue>
#include <set>
#include <string>
#include <cstdlib>
#include <stack>
using namespace std;

#define fi(i,a,b) for(int i=(int)a;i<=(int)b;i++)
#define fd(i,a,b) for(int i=(int)a;i>=(int)b;i--)
#define rep(i,n)  for(int i=0;i<n;i++)
#define SET(a) memset(a,-1,sizeof(a))
#define ALL(a) a.begin(),a.end()
#define CLR(a) memset(a,0,sizeof(a))
#define FILL(a,v) memset(a,v,sizeof(a))
#define READ(f) freopen(f, "r", stdin)
#define WRITE(f) freopen(f, "w", stdout)
#define INF (1<<29)
#define EPS 1e-9
#define PI acos(-1.0)
//stl
 #define sz(a) int((a).size())
 #define pb push_back
 #define all(c) ((c).begin(),(c).end())
 #define tr(c,i) for(typeof((c).begin()) i = (c).begin(); i != (c).end(); i++)
 #define present(c,x) ((c).find(x) != (c).end())
 #define cpresent(c,x) (find(all(c),x) != (c).end())
 #define pf printf
 #define sf scanf


typedef long long ll;
typedef vector<int> vi;
typedef pair<int, int> ii;
typedef vector<ii>    vii;
typedef vector<vi> vvi;
typedef vector<vii> vvii;
typedef map<string,int> msi;

int main()
{
    int t;
    int a[40],d[40];
    rep(i,40)a[i]=d[i]=0;
    a[0]=d[1]=0;
    d[0]=a[1]=1;
    fi(i,2,31)
    {
        a[i]=d[i-1]+a[i-2];
        d[i]=2*a[i-1]+d[i-2];
    }
    while(1)
    {

        cin>>t;
        if(t==-1) break;
        cout<<d[t]<<endl;
    }
  return 0;
}