CodeForces

Indian summer is such a beautiful time of the year! A girl named Alyona is walking in the forest and picking a bouquet from fallen leaves. Alyona is very choosy — she doesn't take a leaf if it matches the color and the species of the tree of one of the leaves she already has. Find out how many leaves Alyona has picked.

Input

The first line contains an integer n (1 ≤ n ≤ 100) — the number of leaves Alyona has found. The next n lines contain the leaves' descriptions. Each leaf is characterized by the species of the tree it has fallen from and by the color. The species of the trees and colors are given in names, consisting of no more than 10 lowercase Latin letters. A name can not be an empty string. The species of a tree and the color are given in each line separated by a space.

Output

Output the single number — the number of Alyona's leaves.

Examples

Input

5 
birch yellow 
maple red 
birch yellow 
maple yellow 
maple green

Output

4

Input

3 
oak yellow 
oak yellow 
oak yellow

Output

1
这个map很快的，map的键不允许重复，所以有重复的直接过滤了，把两个字符串加起来达到合并的效果，然后插入map,再计算个数就行了

#include <map>
#include <string>
#include <cstdio>
#include <cstring>
#include <iostream>
#include <algorithm>
using namespace std;
map<string,int> m;

int main()
{
    int n;
    cin>>n;
    getchar();
    for(int i=0;i<n;i++)
    {
        string str;
        getline(cin,str);
        m[str]=1;//通过数组下标加入map，也可以用insert函数插入：m.insert(make_pair(str,1));
    }
    int cnt=0;
    for(map<string,int>::iterator it=m.begin();it!=m.end();++it)
    {
        //cout<< it->first<<" "<<it->second<<endl;
        cnt++;
    }
    cout<<cnt<<endl;
    return 0;
}