#include<bits/stdc++.h>
using namespace std;

int main()
{
    string first_liine, second_line, third_line, output;
    vector<int> name_values;
    vector<int> found_values;

    //int name_values1[10], name_values2[10], name_values[20], found_values[20];

    cin>>first_liine>>second_line>>third_line;

    int size1=first_liine.size(), size2=second_line.size(), size3=third_line.size();

    for(int i=0; i<size1; i++)
    {
//        name_values[i]=first_liine[i];
        name_values.push_back(first_liine[i]);
    }

    for(int i=size1; i<size1+size2; i++)
    {
//        name_values[i]=second_line[i];
        name_values.push_back(second_line[i]);
    }

    for(int i=0; i<size3; i++)
    {
        //found_values[i]=third_line[i];
        found_values.push_back(third_line[i]);
    }

    sort(name_values.begin(), name_values.end());
    sort(found_values.begin(),found_values.end());

    //sort(name_values, name_values+sizeof(name_values)/sizeof(name_values[0]));
    //sort(found_values, found_values+sizeof(found_values)/sizeof(found_values[0]));

    for(int i=0; i<size1+size2; i++)
    {
        if(name_values[i]!=found_values[i])
        {
            output="NO";
            break;
        }
        else
            output="YES";
    }
    cout<<output;
}