72 lines
1.2 KiB
C++
72 lines
1.2 KiB
C++
#include <bits/stdc++.h>
|
|
using namespace std;
|
|
|
|
int main()
|
|
{
|
|
int n, m;
|
|
cin >> n >> m;
|
|
|
|
string beginWord, endWord;
|
|
cin >> beginWord >> endWord;
|
|
|
|
unordered_set<string> words;
|
|
for (int i = 0; i < n; i++)
|
|
{
|
|
string s;
|
|
cin >> s;
|
|
words.insert(s);
|
|
}
|
|
words.insert(beginWord);
|
|
|
|
unordered_map<string, list<string>> adj;
|
|
for (auto &word : words)
|
|
{
|
|
for (int j = 0; j < m; j++)
|
|
{
|
|
string aux = word;
|
|
for (char c = 'a'; c <= 'z'; c++)
|
|
{
|
|
aux[j] = c;
|
|
if (words.count(aux))
|
|
{
|
|
adj[word].push_back(aux);
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
queue<string> q;
|
|
unordered_set<string> seen;
|
|
q.push(beginWord);
|
|
seen.insert(beginWord);
|
|
|
|
int depth = 1;
|
|
while (!q.empty())
|
|
{
|
|
int nodes = q.size();
|
|
while (nodes--)
|
|
{
|
|
string s = q.front();
|
|
q.pop();
|
|
|
|
if (s == endWord)
|
|
{
|
|
cout << depth << endl;
|
|
return 0;
|
|
}
|
|
|
|
for (auto &t : adj[s])
|
|
{
|
|
if (!seen.count(t))
|
|
{
|
|
q.push(t);
|
|
seen.insert(t);
|
|
}
|
|
}
|
|
}
|
|
depth++;
|
|
}
|
|
|
|
cout << 0 << endl;
|
|
return 0;
|
|
} |