HDOJ 1251 统计难题

求公共前缀数目，最简单的字典树，耗内存，对比一下C++和G++下相同的代码运行结果：

G++虽然快点，但是直接MLE...所以交的时候还要注意选择编译器啊。可能是内存泄漏的原因。

#include<iostream>
#include<cstring>
#include<cstdlib>
#include<cstdio>
#include<cmath>
#include<algorithm>
#define mst(a,b) memset(a,b,sizeof(a))
using namespace std;
typedef long long LL;

struct trie{
    struct trie *next[26];
    int cnt;
    bool exist;
};

trie* CreateNode(){
    trie* node=new trie;
    node->cnt=0;
    node->exist=0;
    memset(node->next,0,sizeof(node->next));
    return node;
}

void InsertNode(trie *root,char *s){
    trie *node=root;
    char *p=s;
    int pos=0;
    while(*p){
        pos = *p-'a';
        if(node->next[pos]==NULL)
            node->next[pos]=CreateNode();
        node=node->next[pos];
        p++;
        node->cnt++;
    }
    node->exist = true;
}

//返回以所查字符串为前缀的次数
int SearchNode(trie *root,char *s){
    trie *node=root;
    char *p=s;
    int pos=0;
    while(*p){
        pos=*p-'a';
        node=node->next[pos];
        p++;
        if(node==NULL) return 0;
    }
    return node->cnt;
}

int main(){
    trie *root=CreateNode();
    char s[11];
    bool flag=1;
    while(gets(s)){
        if(strlen(s)==0) {
            flag=0;
            continue;
        }
        if(flag)
            InsertNode(root,s);
        else printf("%d\n",SearchNode(root,s));
    }
}

HDOJ1075 What are you talking about

给一组词及其对应翻译，然后每次给出一句话，输出这句话对应的翻译。是上一题的简单变形。

仍然用相同的代码来测一下C++和G++：

#include<iostream>
#include<cstring>
#include<cstdlib>
#include<cstdio>
#include<cctype>
#include<cmath>
#include<algorithm>
#define mst(a,b) memset(a,b,sizeof(a))
using namespace std;
typedef long long LL;

struct trie{
    struct trie *next[26];
    char tran[11];
    bool exist;
};

trie* CreateNode(){
    trie* node=new trie;
    node->tran[0]=0;
    node->exist=0;
    memset(node->next,0,sizeof(node->next));
    return node;
}

void InsertNode(trie *root,char *s,char *tr){
    trie *node=root;
    char *p=s;
    int pos=0;
    while(*p){
        pos = *p-'a';
        if(node->next[pos]==NULL)
            node->next[pos]=CreateNode();
        node=node->next[pos];
        p++;
    }
    node->exist = true;
    strcpy(node->tran,tr);
}

char* SearchNode(trie *root,char *s){
    trie *node=root;
    char *p=s;
    int pos=0;
    while(*p){
        pos=*p-'a';
        node=node->next[pos];
        p++;
        if(node==NULL) return 0;
    }
    if(node->exist)
        return node->tran;
    else return NULL;
}

int main(){
    trie *root=CreateNode();
    char s[3005],tran[11],tmp[15],*p;
    scanf("%s",s);
    while(scanf("%s",tran)&&strcmp(tran,"END")){
        scanf("%s",s);
        InsertNode(root,s,tran);
    }

    int pos=0;
    scanf("%s",s);
    getchar();
    while(gets(s)&&strcmp(s,"END")){
        for(int i=0;s[i];i++){
            if(islower(s[i]))
                tmp[pos++]=s[i];
            else{
                tmp[pos]='\0';
                pos=0;
                p=SearchNode(root,tmp);
                if(p)
                    printf("%s",p);
                else printf("%s",tmp);
                printf("%c",s[i]);
            }
        }
        printf("\n");
    }
}