Codeforces Beta Round #4 (Div. 2 Only) C. Registration system 暴力or 字典树or哈希

http://codeforces.com/problemset/problem/4/C

题意：

一个注册系统，给出n个注册的名字，每次检查数据库中是否存在该名字，如果不存在返回OK，加入数据库，否如果存在在该名字后边加1,2,3,,,....然后加入数据库。

思路：

暴力存储查询可过，用字典数存处名字可过，哈希存储查找可过。

暴力：

View Code

#include <iostream>

#include <cstdio>

#include <cstdlib>

#include <cstring>

#include <algorithm>

#include <cmath>

#include <queue>

#include <stack>

#include <set>

#include <map>

#include <string>



#define CL(a,num) memset((a),(num),sizeof(a))

#define iabs(x)  ((x) > 0 ? (x) : -(x))

#define Min(a,b) (a) > (b)? (b):(a)

#define Max(a,b) (a) > (b)? (a):(b)



#define ll long long

#define inf 0x7f7f7f7f

#define MOD 1073741824

#define lc l,m,rt<<1

#define rc m + 1,r,rt<<1|1

#define pi acos(-1.0)

#define test puts("<------------------->")

#define maxn 100007

#define M 1000007

#define N 100007

using namespace std;

//freopen("data.in","r",stdin);





string str[N];

int num[N];

int len;



bool isok(string a,string &b){

    for (int i = 0; i < len; ++i){

        if (str[i] == a){

            char p[10];

            sprintf(p,"%d",num[i]);

            b = a + p;

            num[i]++;

            return false;

        }

    }

    str[len] = a;

    num[len++]++;

    return true;

}

int main(){

    //freopen("data.in","r",stdin);

    int i;

    int n;

    cin>>n;

    string tmp,stre;



    CL(num,0);

    len = 0;

    for (i = 0; i < n; ++i){

        cin>>stre;

        if (isok(stre,tmp)) puts("OK");

        else{

            cout<<tmp<<endl;

        }

    }

    return 0;

}

 

字典数：

View Code

#include <iostream>

#include <cstdio>

#include <cstdlib>

#include <cstring>

#include <algorithm>

#include <cmath>

#include <queue>

#include <stack>

#include <set>

#include <map>

#include <string>



#define CL(a,num) memset((a),(num),sizeof(a))

#define iabs(x)  ((x) > 0 ? (x) : -(x))

#define Min(a,b) (a) > (b)? (b):(a)

#define Max(a,b) (a) > (b)? (a):(b)



#define ll long long

#define inf 0x7f7f7f7f

#define MOD 1073741824

#define lc l,m,rt<<1

#define rc m + 1,r,rt<<1|1

#define pi acos(-1.0)

#define test puts("<------------------->")

#define maxn 100007

#define M 1000007

#define N 100007

using namespace std;

//freopen("data.in","r",stdin);



struct node{

    int flag;

    node *next[27];

}*head,H[500000];

int t;

char str[40],tmp[10];



node* newnode(){

    node *p = &H[t++];

    for (int i = 0; i < 26; ++i){

        p->next[i] = NULL;

        p->flag = 0;

    }

    return p;

}

bool find(char *s,char *tmp){

    int i,k;

    int len = strlen(s);

    node *p = head;

    for (i = 0; i < len; ++i){

        k = s[i] - 'a';

        if (p->next[k] == NULL) return false;

        p = p->next[k];

    }

    if (p->flag != 0){

        sprintf(tmp,"%d",p->flag);

        p->flag++;

        return true;

    }

    else return false;

}

void insert(char *s){

    int i,k;

    int len = strlen(s);

    node *p = head;

    for (i = 0; i < len; ++i){

        k = s[i] - 'a';

        if (p->next[k] == NULL) p->next[k] = newnode();

        p = p->next[k];

    }

    p->flag++;

}

int main(){

    //freopen("data.in","r",stdin);

    int i;

    int n;

    cin>>n;

    t = 0;



    head = newnode();

    for (i = 0; i < n; ++i){

        scanf("%s",str);

        if (find(str,tmp)) printf("%s%s\n",str,tmp);

        else{

            puts("OK");

            insert(str);

        }

    }

    return 0;

}

 

哈希：

View Code

#include <iostream>

#include <cstdio>

#include <cstdlib>

#include <cstring>

#include <algorithm>

#include <cmath>

#include <queue>

#include <stack>

#include <set>

#include <map>

#include <string>



#define CL(a,num) memset((a),(num),sizeof(a))

#define iabs(x)  ((x) > 0 ? (x) : -(x))

#define Min(a,b) (a) > (b)? (b):(a)

#define Max(a,b) (a) > (b)? (a):(b)



#define ll long long

#define inf 0x7f7f7f7f

#define MOD 1073741824

#define lc l,m,rt<<1

#define rc m + 1,r,rt<<1|1

#define pi acos(-1.0)

#define test puts("<------------------->")

#define maxn 100007

#define M 1000007

#define N 100007

using namespace std;

//freopen("data.in","r",stdin);



struct node{

    string str;

    int num;

    node *next;

}*head[N + 2],H[N];

int t;

char str[40],tmp[10];



bool Cha(int sum,char *s,char*tmp){

    sum %= N;

    if (sum < 0) sum = -sum;

    node *p;

    for (p = head[sum]; p != NULL; p = p->next){

        if (p->str == s){

            sprintf(tmp,"%d",p->num);

            p->num++;

            return true;

        }

    }

    return false;

}

void Gua(int sum,char *s){

    sum %= N;

    if (sum < 0) sum = -sum;

    node *p = &H[t++];

    p->str = s;

    p->num = 1;

    p->next = head[sum];

    head[sum] = p;

}

int main(){

    //freopen("data.in","r",stdin);

    int n,i,j;

    CL(head,0); t = 0;

    scanf("%d",&n);

    int sum = 0;

    for (i = 0; i < n; ++i){

        scanf("%s",str);

        int len = strlen(str);

        sum = 0;

        for (j = 0; j < len; ++j){

            sum += str[j] - '0';

        }

        if (Cha(sum,str,tmp)) printf("%s%s\n",str,tmp);

        else{

            puts("OK");

            Gua(sum,str);

        }

    }

    return 0;

}