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

#define MAX_WORDS 5000
#define MAX_WORD_LEN 11

int dfs(char* word, char* target, char wordList[][MAX_WORD_LEN], int wordCount, int* visited, int length) {
    if (strcmp(word, target) == 0) {
        return length;
    }
    
    int minLength = INT_MAX;
    char temp[MAX_WORD_LEN];
    strcpy(temp, word);
    
    for (int i = 0; i < strlen(word); i++) {
        char original = temp[i];
        for (char c = 'a'; c <= 'z'; c++) {
            if (c == original) continue;
            
            temp[i] = c;
            
            for (int j = 0; j < wordCount; j++) {
                if (strcmp(temp, wordList[j]) == 0 && !visited[j]) {
                    visited[j] = 1;
                    int result = dfs(temp, target, wordList, wordCount, visited, length + 1);
                    if (result != INT_MAX && result < minLength) {
                        minLength = result;
                    }
                    visited[j] = 0;
                    break;
                }
            }
        }
        temp[i] = original;
    }
    
    return minLength;
}

int solution(char* beginWord, char* endWord, char wordList[][MAX_WORD_LEN], int wordCount) {
    int foundEnd = 0;
    for (int i = 0; i < wordCount; i++) {
        if (strcmp(endWord, wordList[i]) == 0) {
            foundEnd = 1;
            break;
        }
    }
    
    if (!foundEnd) return 0;
    
    int visited[MAX_WORDS] = {0};
    int result = dfs(beginWord, endWord, wordList, wordCount, visited, 1);
    return result == INT_MAX ? 0 : result;
}

int main() {
    char beginWord[MAX_WORD_LEN], endWord[MAX_WORD_LEN];
    char line[10000];
    
    fgets(beginWord, sizeof(beginWord), stdin);
    beginWord[strcspn(beginWord, "\n")] = 0;
    
    fgets(endWord, sizeof(endWord), stdin);
    endWord[strcspn(endWord, "\n")] = 0;
    
    fgets(line, sizeof(line), stdin);
    
    char wordList[MAX_WORDS][MAX_WORD_LEN];
    int wordCount = 0;
    
    char* ptr = strchr(line, '[');
    if (ptr) {
        ptr++;
        char* end = strchr(ptr, ']');
        if (end) *end = '\0';
        
        char* token = strtok(ptr, ",");
        while (token && wordCount < MAX_WORDS) {
            while (*token == ' ' || *token == '"') token++;
            char* wordEnd = token + strlen(token) - 1;
            while (wordEnd > token && (*wordEnd == ' ' || *wordEnd == '"')) {
                *wordEnd = '\0';
                wordEnd--;
            }
            if (strlen(token) > 0) {
                strcpy(wordList[wordCount], token);
                wordCount++;
            }
            token = strtok(NULL, ",");
        }
    }
    
    int result = solution(beginWord, endWord, wordList, wordCount);
    printf("%d\n", result);
    
    return 0;
}