用了许多库函数

sort(): 排序vector数组
erase(): 分别除掉a,b两个数组中重复的值
insert(): 合并a,b两个数组

#include <iostream>
#include <cctype>
#include <vector>
#include <algorithm>
using namespace std;
const int N = 10010;
int n,m;
vector<string> a,b;

int main()
{
    cin>>n>>m;
    string s;
    //输入并转换为小写
    for(int i=0; i<n; i++)
    {
        cin>>s;
        for(int j=0; j<s.length(); j++)
            if(isupper(s[j])) s[j]+=32;
        a.push_back(s);
    }

    for(int i=0; i<m; i++)
    {
        cin>>s;
        for(int j=0; j<s.length(); j++)
            if(isupper(s[j])) s[j]+=32;
        b.push_back(s);
    }

    sort(a.begin(), a.end()), sort(b.begin(), b.end());
    a.erase(unique(a.begin(), a.end()), a.end());
    b.erase(unique(b.begin(), b.end()), b.end());


    a.insert(a.end(), b.begin(), b.end());
    sort(a.begin(), a.end());
    //并集个数
    int num = unique(a.begin(), a.end())-a.begin();

    cout<<a.size()-num<<"\n"<<num;

    return 0;

}