AcWing 168. 生日蛋糕 (dfs剪枝)
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AcWing 168. 生日蛋糕
问题
代码
#include <iostream>
#include <cstdio>
#include <queue>
#include <cstring>
#include <algorithm>
#include <cmath>
using namespace std;
const int N = 25,INF = 1e9;
int n,m;
int minv[N],mins[N];
int R[N],H[N];
int ans = INF;
void dfs(int u,int v,int s)
{
// cout<<1;
if(v+minv[u] > n) return;
if(s+mins[u] >= ans) return;
if(s+2*(n-v)/(R[u+1]) >= ans) return;
if(!u)
{
if(v==n) ans = s;
return;
}
for(int r=min(R[u+1]-1,(int)sqrt(n-v));r>=u;r--)
{
for(int h=min(H[u+1]-1,(n-v)/r/r);h>=u;h--)
{
int t = 0;
if(u==m)
t = r*r;
R[u] = r,H[u] = h;
dfs(u-1,v+r*r*h,s+2*r*h+t);
}
}
}
int main()
{
cin >> n >> m;
for(int i=1;i<=m;i++)
{
minv[i] = minv[i-1] + i*i*i;
mins[i] = mins[i-1] + 2*i*i;
}
R[m+1] = H[m+1] = INF;
dfs(m,0,0);
cout << ans << "\n";
return 0;
}
标签:剪枝,mins,return,int,dfs,168,ans,include 来源: https://www.cnblogs.com/hh13579/p/12398720.html