HDU-1305-Immediate Decodability

HDU-1305-Immediate Decodability

http://acm.hdu.edu.cn/showproblem.php?pid=1305

字典树水题，判断前缀

#include<iostream>#include<cstdio>#include<cstring>#include<cstdlib>using namespace std;struct node{int count;node *childs[2];node(){count=0;for(int i=0;i<2;i++)childs[i]=NULL;}};node *root,*current,*newnode;int flag;void insert(char *str){int i,m;current=root;for(i=0;i<strlen(str);i++){m=str[i]-'0';if(current->childs[m]!=NULL){current=current->childs[m];    if(i==strlen(str)-1||current->count==1){flag=0;break;}}else{newnode=new node;current->childs[m]=newnode;current=newnode;}}current->count=1;}void del(node *head){for(int i=0;i<2;i++)if(head->childs[i]!=NULL)del(head->childs[i]);delete(head);}int main(){int cas=1;char str[15];while(scanf("%s",str)!=EOF){flag=1;root=new node;insert(str);while(scanf("%s",str),strcmp(str,"9")){if(!flag)continue;insert(str);}if(!flag)printf("Set %d is not immediately decodable\n",cas++);elseprintf("Set %d is immediately decodable\n",cas++);del(root);}return 0;}