## implementation

...

#define repeat(i, n) for (int i = 0; (i) < int(n); ++(i))
#define repeat_reverse(i, n) for (int i = (n)-1; (i) >= 0; --(i))
template <class T> inline void setmax(T & a, T const & b) { a = max(a, b); }
template <class T> inline void setmin(T & a, T const & b) { a = min(a, b); }

constexpr int inf = 1e9+7;
int minimumLength(string const & text, vector<string> const & keys) {
int n = text.length();
vector<uint16_t> found(n + 1);
for (int l = 0; l < n; ) {
if (text[l] == ' ') {
++ l;
} else {
int r = text.find(' ', l);
if (r == string::npos) r = n;
repeat (k, keys.size()) {
if (text.compare(l, r - l, keys[k]) == 0) {
found[r] |= 1 << k;
}
}
l = r;
}
}
vector<vector<int> > next(keys.size(), vector<int>(n + 30, inf));
repeat (k, keys.size()) {
if (found[n] & (1 << k)) next[k][n] = n;
}
repeat_reverse (i, n) {
repeat (k, keys.size()) {
next[k][i] = next[k][i + 1];
if (found[i] & (1 << k)) next[k][i] = i;
}
}
int result = inf;
repeat (i, n) {
int acc = 0;
repeat (k, keys.size()) {
setmax(acc, next[k][i + keys[k].length()]);
}
setmin(result, acc - i);
}
if (result > n) result = -1;
return result;
}

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