HDU 1226 搜索

来源：互联网发布：网络硬盘服务器软件编辑：程序博客网时间：2024/06/05 19:35

BFS用余数来判重，因为n最大5000，只需要存储5000以内的余数即可；

n==0 时特殊考虑一下

#include "queue"#include "string"#include "iostream"using namespace std;struct node{int mod;string ans;};int n,c,flag;string ans;int mark[5010],f[5010];void bfs(){queue<node>q;node cur,next;int i;for (i=1;i<16;i++)if (f[i]==1){mark[i%n]=1;cur.mod=i%n;cur.ans="";if (i<10)cur.ans+=i+'0';else cur.ans+=i+'A'-10;q.push(cur);}while (!q.empty()){cur=q.front();q.pop();if (flag==1 && cur.ans.size()>ans.size()) continue;if (cur.mod==0){if (flag==0) ans=cur.ans;flag=1;if (ans.size()>cur.ans.size() ||  (ans.size()==cur.ans.size()  && ans>cur.ans))ans=cur.ans;}for (i=0;i<16;i++)if (f[i]==1){next=cur;if (i<10)next.ans+=i+'0';else next.ans+=i+'A'-10;next.mod=(cur.mod*c+i)%n;if ((next.ans.size()<=500 && mark[next.mod]==0) || next.mod==0){mark[next.mod]=1;q.push(next);}}}}int main(){int Case,i,m;char ch;scanf("%d",&Case);while (Case--){scanf("%d%d",&n,&c);scanf("%d",&m);memset(f,0,sizeof(f));// 记录该数字是否可用for (i=1;i<=m;i++){getchar();scanf("%c",&ch);if (ch<='9' && ch>='0') f[ch-'0']=1;else f[ch-'A'+10]=1;}if (n==0){if (f[0]==1) printf("0\n");else printf("give me the bomb please\n");continue;}flag=0;memset(mark,0,sizeof(mark));// 记录余数时候出现过bfs();if (flag==0) printf("give me the bomb please\n");else cout<<ans<<endl; }return 0;}

0 0