#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <ctype.h>

void getLetterCount(const char* s, int count[26]) {
    for (int i = 0; i < 26; i++) count[i] = 0;
    
    for (int i = 0; s[i]; i++) {
        if (isalpha(s[i])) {
            count[tolower(s[i]) - 'a']++;
        }
    }
}

int isCompleting(const char* word, int requiredCount[26]) {
    int wordCount[26];
    getLetterCount(word, wordCount);
    
    for (int i = 0; i < 26; i++) {
        if (wordCount[i] < requiredCount[i]) {
            return 0;
        }
    }
    return 1;
}

char* shortestCompletingWord(char* licensePlate, char** words, int wordsSize) {
    char* shortest = NULL;
    int shortestLen = INT_MAX;
    
    for (int i = 0; i < wordsSize; i++) {
        // Extract and count letters from license plate for each word
        int requiredCount[26];
        getLetterCount(licensePlate, requiredCount);
        
        if (isCompleting(words[i], requiredCount)) {
            int len = strlen(words[i]);
            if (len < shortestLen) {
                shortest = words[i];
                shortestLen = len;
            }
        }
    }
    
    return shortest;
}

int main() {
    char licensePlate[100];
    fgets(licensePlate, sizeof(licensePlate), stdin);
    licensePlate[strcspn(licensePlate, "\n")] = 0;
    
    // Parse words (simplified)
    char* words[] = {"word", "world", "programming"};
    int wordsSize = 3;
    
    char* result = shortestCompletingWord(licensePlate, words, wordsSize);
    printf("%s\n", result);
    
    return 0;
}