POJ-1011-Sticks

来源：互联网发布：影视制作软件编辑：程序博客网时间：2024/05/16 14:52

DFS超级经典的一个题，需要N多剪枝才行，具体看代码吧~剪枝都在return中~

代码：

#include<cstdio>#include<cstring>#include<iostream>#include<algorithm>using namespace std;const int maxn=65;int n,a[maxn],sum[maxn];bool vis[maxn],getans;void DFS(int res,int now,int val,int st){    if(res==val||getans)    {getans=1;return;    }    int last=-1;    for(int i=st;i>=1;i--)    {if(!vis[i]){    if(a[i]==last)continue;    if(now+a[i]<val)    {vis[i]=1;DFS(res-a[i],now+a[i],val,i-1);if(getans)    return;vis[i]=0;last=a[i];    }    else if(now+a[i]==val)    {vis[i]=1;DFS(res-a[i],0,val,n);if(getans)    return;vis[i]=0;last=a[i];    }    if(!now)return;}    }}int main(){    while(scanf("%d",&n)&&n)    {getans=0;for(int i=1;i<=n;i++){    scanf("%d",&a[i]);    sum[i]=sum[i-1]+a[i];}sort(a+1,a+n+1);for(int i=n;i>=1;i--){    if(sum[n]%i==0)    {if(sum[n]/i<a[n])    continue;memset(vis,0,sizeof(vis));DFS(sum[n],0,sum[n]/i,n);if(getans){    printf("%d\n",sum[n]/i);    break;}    }}    }    return 0;}