10252

/****************************************************
 * Author      : Kaidul Islam
 * University  : Khulna University of Engr. and Tech.
*****************************************************/
#include <bits/stdc++.h>
using namespace std;
#define rep(i, n) for(__typeof(n) i = 0; i < (n); i++)
#define rep1(i, n) for(__typeof(n) i = 1; i <= (n); i++)
#define FOR(i, a, b) for(__typeof(b) i = (a); i <= (b); i++)
#define forstl(i, s) for (__typeof ((s).end ()) i = (s).begin (); i != (s).end (); ++i)
#define INF (1 << 30)
#define PI acos(-1.0)
#define pb push_back
#define ppb pop_back
#define all(x) x.begin(), x.end()
#define mem(x, y) memset(x, y, sizeof x)
#define eps 1e-9
#define pii pair<int, int>
#define couple make_pair
#define X first
#define Y second
#define vi vector<int>
#define vpii vector< pii >
#define si set<int>
#define SDi(x) sf("%d", &x)
#define SD2(x, y) sf("%d %d", &x, &y)
#define SD3(x, y, z) sf("%d %d %d", &x, &y, &z)
#define SDs(x) sf("%s", x)
#define pf printf
#define print(x) pf("%d ", x)
#define println(x) pf("%d\n", x)
#define newLine pf("\n")
#define sf scanf
#define READ(f) freopen(f, "r", stdin)
#define WRITE(f) freopen(f, "w", stdout)
#if ( _WIN32 or __WIN32__ )
    #define LLD "%I64d"
#else
    #define LLD "%lld"
#endif
#define SDl(x) sf(LLD, &x)
#define MAX6 1000000
#define MAX7 10000000
#define MAX9 1000000000
#define MOD7 (MAX7 + 7)
#define MOD9 (MAX9 + 9)
typedef long long i64;
typedef unsigned long long ui64;
const i64 INF64 = (i64)1E18;

string toString(int num) {
    ostringstream convert;
    convert << num;
    return convert.str();
}

// BitMask
int Set(int N, int pos) {
    return N = N | (1 << pos);
}
int Reset(int N, int pos) {
    return N = N & ~(1 << pos);
}
int Check(int N, int pos) {
    return (N & (1 << pos));
}
int toggle(int N, int pos) {
    if( Check(N, pos) )
        return N = Reset(N, pos);
    return N = Set(N, pos);
}

// direction array
//int dx[] = {0, -1, 0, 1};
//int dy[] = {-1, 0, 1, 0};
//int Dx[] = {0, -1, -1, -1, 0, 1, 1, 1};
//int Dy[] = {-1, -1, 0, 1, 1, 1, 0, -1};
//int row, col;
//bool isValid(int i, int j) {
//    return i >= 0 and j >= 0 and i < row and j < col;
//}

/** Implementation **/

int main() {
    string a, b, ans;
    map <int ,int> mA, mB;
    int lenA, lenB, len;
    while(getline (cin, a)) {
        getline (cin, b);
        lenA = a.size(), lenB = b.size();
        mA = map <int ,int> ();
        mB = map <int ,int> ();
        for(int i = 0; i < lenA; ++i) ++mA[a[i] - 'a'];
        for(int i = 0; i < lenB; ++i) ++mB[b[i] - 'a'];
        ans = "";
        for(int i = 0; i < 26; ++i) {
            len = min(mA[i], mB[i]);
            for(int j = 0; j < len; ++j) ans += i + 'a';
        }
        pf("%s\n", ans.c_str());
    }

    return 0;
}