Codeforces 766D Mahmoud and a Dictionary 2017-02-21 14:03 107人阅读 评论(0) 收藏

D. Mahmoud and a Dictionary

time limit per test

4 seconds

memory limit per test

256 megabytes

input

standard input

output

standard output

Mahmoud wants to write a new dictionary that contains n words and relations between them. There are two types of relations:
synonymy (i. e. the two words mean the same) and antonymy (i. e. the two words mean the opposite). From time to time he discovers a new relation between two words.

He know that if two words have a relation between them, then each of them has relations with the words that has relations with the other. For example, if like means love and love is
the opposite of hate, then like is also the opposite of hate.
One more example: if love is the opposite of hate and hate is
the opposite of like, then love means like,
and so on.

Sometimes Mahmoud discovers a wrong relation. A wrong relation is a relation that makes two words equal and opposite at the same time. For example if he knows that love means like and like is
the opposite of hate, and then he figures out that hate means like,
the last relation is absolutely wrong because it makes hate and like opposite and have the
same meaning at the same time.

After Mahmoud figured out many relations, he was worried that some of them were wrong so that they will make other relations also wrong, so he decided to tell every relation he figured out to his coder friend Ehab and for every
relation he wanted to know is it correct or wrong, basing on the previously discovered relations. If it is wrong he ignores it, and doesn't check with following relations.

After adding all relations, Mahmoud asked Ehab about relations between some words based on the information he had given to him. Ehab is busy making a Codeforces round so he asked you for help.

Input

The first line of input contains three integers n, m and q (2 ≤ n ≤ 105, 1 ≤ m, q ≤ 105)
where n is the number of words in the dictionary, m is
the number of relations Mahmoud figured out and q is the number of questions Mahmoud asked after telling all relations.

The second line contains n distinct words a1, a2, ..., an consisting
of small English letters with length not exceeding 20, which are the words in the dictionary.

Then m lines follow, each of them contains an integer t (1 ≤ t ≤ 2)
followed by two different words xi and yi which
has appeared in the dictionary words. If t = 1, that means xi has
a synonymy relation with yi,
otherwise xi has an antonymy
relation with yi.

Then q lines follow, each of them contains two different words which has appeared in the dictionary. That are the pairs
of words Mahmoud wants to know the relation between basing on the relations he had discovered.

All words in input contain only lowercase English letters and their lengths don't exceed 20 characters. In all relations and in all
questions the two words are different.

Output

First, print m lines, one per each relation. If some relation is wrong (makes two words opposite and have the same meaning
at the same time) you should print "NO" (without quotes) and ignore it, otherwise print "YES"
(without quotes).

After that print q lines, one per each question. If the two words have the same meaning, output 1.
If they are opposites, output 2. If there is no relation between them, output 3.

See the samples for better understanding.

Examples

input

3 3 4
hate love like
1 love like
2 love hate
1 hate like
love like
love hate
like hate
hate like

output

YES
YES
NO
1
2
2
2

input

8 6 5
hi welcome hello ihateyou goaway dog cat rat
1 hi welcome
1 ihateyou goaway
2 hello ihateyou
2 hi goaway
2 hi hello
1 hi hello
dog cat
dog hi
hi hello
ihateyou goaway
welcome ihateyou

output

YES
YES
YES
YES
NO
YES
3
3
1
1
2

————————————————————————————————————

题目的意思是给你n个字符串，然后给你m组关系相同或相反，判这两个字符串关系是否冲突，如果不冲突建立关系，最后判两个给出的字符串的关系

思路：可以把一个字符串拆成两个点，a和非a，然后并查集维护。

也可以使用带权的并查集做

#include <iostream>
#include <cstdio>
#include <cstring>
#include <cmath>
#include <algorithm>
#include <queue>
#include <stack>
#include <string>
#include <set>
#include <map>
using namespace std;

map<string,int>mp;
int pre[200005];
int m,n,k;

void init()
{
    for(int i=0; i<200005; i++)
        pre[i]=i;
}

int fin(int x)
{
    if(x!=pre[x])
        pre[x]=fin(pre[x]);
    return pre[x];
}

int main()
{
string s1,s2;
int f;
    while(~scanf("%d%d%d",&n,&m,&k))
    {
        init();
        for(int i=0; i<n; i++)
        {
            cin>>s1;
            mp[s1]=i;
        }

        for(int i=0; i<m; i++)
        {
            cin>>f>>s1>>s2;
            int x=fin(mp[s1]),y=fin(mp[s2]);
            int a=fin(mp[s1]+100000),b=fin(mp[s2]+100000);
            if(f==1)
            {
                if(x==b||a==y)
                    printf("NO\n");
                else
                {
                    printf("YES\n");
                    pre[x]=y;
                    pre[a]=b;
                }
            }
            else
            {
                if(x==y||a==b)
                {
                    printf("NO\n");
                }
                else
                {
                    printf("YES\n");
                    pre[x]=b;
                    pre[a]=y;
                }
            }
        }

        for(int i=0;i<k;i++)
        {
              cin>>s1>>s2;
            int x=fin(mp[s1]),y=fin(mp[s2]);
            int a=fin(mp[s1]+100000),b=fin(mp[s2]+100000);
            if(x==y&&a==b)
                printf("1\n");
            else if(x==b&&a==y)
                printf("2\n");
            else
                printf("3\n");
        }

    }
    return 0;
}