bzoj2660

dp

看了挺长时间的,这篇写的很好:http://97littleleaf11.xyz/oi/bzoj-2660/

我们先把n按照斐波那契数列贪心分解,然后发现可以把现在组合的斐波那契数分解成两个较小的,具体看博客,然后就是dp转移,上面的博客图画的很清楚了,转移就很方便

#include<cstdio>
#include<cstring>
#include<algorithm>
#include<iostream>
using namespace std;
const int N = 110;
int top;
long long n;
long long f[N], dp[N][2], st[N];
int main()
{
    cin >> n;
    f[1] = 1;
    f[2] = 2;
    for(int i = 3; i <= 88; ++i) f[i] = f[i - 1] + f[i - 2];
    for(int i = 88; i; --i) if(n - f[i] >= 0) 
    {
        n -= f[i];
        st[++top] = i;
    }
    reverse(st + 1, st + top + 1);
    dp[1][1] = 1;
    dp[1][0] = (st[1] - 1) >> 1;
    for(int i = 2; i <= top; ++i)
    {
        dp[i][1] = dp[i - 1][0] + dp[i - 1][1];
        dp[i][0] = dp[i - 1][0] * ((st[i] - st[i - 1]) >> 1) + dp[i - 1][1] * ((st[i] - st[i - 1] - 1) >> 1);
    }
    cout << dp[top][0] + dp[top][1];
    return 0;
}
View Code
原文地址:https://www.cnblogs.com/19992147orz/p/7508921.html