hdu1247+hdu1075 字典树基础

#include <stdio.h>//hdu1075
#include<string.h>
#include<algorithm>
using namespace std;
struct tree
{
int flag,num;//flag用于标记是否为单词结尾
tree *next[26];//指向26个字母
};
tree *root;
char s[1000000][20],b[4000];
void creat(char str[],int temp)
{
int i,x,j;
int len = strlen(str);
tree *p = root;
tree *q;
for(i = 0; i < len; i++)
{
x = str[i] - 'a';
if(!p->next[x])
{
q = (tree*)malloc(sizeof(tree));//这个一定不能少，也不能放在循环外面。我刚开始没理解，在这里调试了很久
q->flag = 0;
q->num = temp;//记录单词的编号，其实这个地方不记录，在循环完后记录flag = 1 的地方记录也可以
for(j = 0; j < 26; j++)
{
q->next[j] = NULL;
}
p->next[x] = q;
p = q;
}
else if(p->next[x]->flag==0)
{
p->next[x]->num = temp;
p = p->next[x];
}
}
p->flag = 1;
}
int find(char str[])
{
int x,i,len = strlen(str);
tree *p = root;
for(i = 0; i < len; i++)
{
x = str[i] - 'a';
if(p->next[x]) p = p->next[x];
else return 0;
}
if(p->flag) return p->num;
else return 0;
}
int main()
{
//	freopen("t.txt","r",stdin);
int i,j,len,text;
char f[50],a[1000];
root = (tree*)malloc(sizeof(tree));
root->flag = 0;
root->num = 0;
for(i = 0; i < 26; i++)
{
root->next[i] = NULL;
}
gets(a);
j = 1;
while(1)
{
scanf("%s",s[j]);
if(s[j][0] == 'E') break;
j++;
scanf("%s",s[j]);
creat(s[j],j);
j++;
}
getchar();
gets(a);
while(1)
{
gets(b);
if(b[0] == 'E') break;
len = strlen(b);
for(j = 0, i = 0; i < len; i++)
{
if(b[i] >= 'a' && b[i] <= 'z')
{
f[j++] = b[i];
}
else
{
f[j] = '\0';
if(text = find(f))
{
printf("%s",s[text - 1]);
}
else printf("%s",f);
printf("%c",b[i]);
memset(f,0,sizeof(f));
j = 0;
}
}
printf("\n");
}
return 0;

}

#include<stdio.h>//hdu1247 类似的题目
#include<string.h>
#include<algorithm>
#include<stdlib.h>
using namespace std;
struct tree
{
bool flag;
tree* next[26];
};
tree * root;
char s[50005][20];
void creat(char str[])
{
int x,i,j,len = strlen(str);
tree* p = root;
tree* q = (tree*)malloc(sizeof(tree));
for(i = 0; i < len; i++)
{
x = str[i] - 'a';
if(!p->next[x])
{
q = (tree*)malloc(sizeof(tree));
for(j = 0; j < 26; j++)
{
q->next[j] = NULL;
}
q->flag = 0;
p->next[x] = q;
p = q;
}
else p = p->next[x];
}
p->flag= 1;
}
int search(char str[],int from,int end)
{
int i,j,x;
tree *p = root;
for(i = from; i <= end; i++)
{
x = str[i] - 'a';
if(p->next[x] == NULL)
{
return 0;
}
p = p->next[x];
}
if(p->flag == 1)
{
return 1;
}
return 0;
}
int main()
{
//	freopen("t.txt","r",stdin);
int len,i,j,num;

root = (tree*)malloc(sizeof(tree));
root->flag = 0;
for(i = 0; i < 26; i++)
{
root->next[i] = NULL;
}

j = 0;
while(~scanf("%s",s[j++]))
{
creat(s[j - 1]);
}
num = j;
for(i = 0; i < num; i++)
{
len = strlen(s[i]);
if(len < 2) continue;
for(j = 0; j < len - 1; j++)
{
if(search(s[i],0,j) && search(s[i],j+1,len-1))
{
printf("%s\n",s[i]);
break;
}

}
}
return 0;
}