蒜头爬楼梯

#include<iostream>#include<cstdio>using namespace std;#define MAXN 50int dp(int i){        if(i==1) return 1;        if(i==2) return 2;        dp(i)=dp(i-1)+dp(i-2);    }int main(){    int n;    n=scanf("%d",&n);    printf("%d",dp(n));}

使用数组记忆重复结果，优化

<pre name="code" class="cpp">#include<iostream>#include<cstdio>using namespace std;#define MAXN 50int result[100]={0};int dp(int i){        int res;        if(result[i]) return result[i];        if(i==0) return 1;        if(i==1) return 1;        res=dp(i-1)+dp(i-2);        result[i]=res;        return res;    }int main(){    int n;    scanf("%d",&n);    printf("%d",dp(n));}