搜索剪枝之1011

发布时间:2016-12-10 9:15:55 编辑:www.fx114.net 分享查询网我要评论
本篇文章主要介绍了"搜索剪枝之1011",主要涉及到搜索剪枝之1011方面的内容,对于搜索剪枝之1011感兴趣的同学可以参考一下。

其实,搜索可以认为是DFS,递归穷举所有情况的同时,通过剪枝舍去那些不可能的情况,来降低搜索的复杂度。 Sticks Time Limit: 1000MS   Memory Limit: 10000K Total Submissions: 111462   Accepted: 25581 Description George took sticks of the same length and cut them randomly until all parts became at most 50 units long. Now he wants to return sticks to the original state, but he forgot how many sticks he had originally and how long they were originally. Please help him and design a program which computes the smallest possible original length of those sticks. All lengths expressed in units are integers greater than zero. Input The input contains blocks of 2 lines. The first line contains the number of sticks parts after cutting, there are at most 64 sticks. The second line contains the lengths of those parts separated by the space. The last line of the file contains zero. Output The output should contains the smallest possible length of original sticks, one per line. Sample Input 9 5 2 1 5 2 1 5 2 1 4 1 2 3 4 0 Sample Output 6 5 #include<iostream> using namespace std; int n[100001]; bool used[100001]; void sort(int a[],int num){ for(int i=0;i<num-1;i++){ for(int j=0;j<num-i-1;j++){ if(a[j]<a[j+1]){ int temp=a[j]; a[j]=a[j+1]; a[j+1]=temp; } } } } bool concate(int unused,int left,int targetLen,int totalNum){ int i=0; if(left==0&&unused==0){ return true; }else if(left==0){ left=targetLen; } for(i=0;i<totalNum;i++){ if(!used[i]){ if(left<n[i]) continue; left=left-n[i]; used[i]=true; if(concate(unused-1,left,targetLen,totalNum)) return true; } } used[i]=false; return false; } int main(){ int sNum,sumLen=0; while(cin>>sNum){ if(sNum==0) break; else{ for(int i=0;i<100001;i++){ used[i]=false; n[i]=0; } for(int i=0;i<sNum;i++){ cin>>n[i]; sumLen+=n[i]; } sort(n,sNum); if(sNum==1){ cout<<n[0]<<endl; continue; } for(int i=sumLen/n[0];(i>=2)&&(sumLen%i==0);i--){ if(concate(sNum,sumLen/i,sumLen/i,sNum)){ cout<<sumLen/i<<endl; break; } } } sumLen=0; } } 顺便说下,并没有ac,但是,我测试了十来组数据,都是正确的,检查也看不出漏了哪些情况,所以,就这样贴上来吧

上一篇:WEB测试应该注意哪些地方,怎样才能做好WEB测试
下一篇:为什么C++中空类和空结构体大小为1?

相关文章

相关评论