Minimum Window Substring

Find the shortest contiguous substring of text that contains every character of pattern, including repeats. If several are equally short, return the leftmost.

Implement min_window(text, pattern).

Input

text: The text to search. pattern: The characters that must appear.

Output

Return the shortest window, or an empty string if none exists.

Restricciones

1 ≤ length of text, pattern ≤ 100,000 (ASCII)

Ejemplos

Entrada:
text = "ADOBECODEBANC"
pattern = "ABC"

Salida esperada:
expected = "BANC"

Entrada:
std::string text = "ADOBECODEBANC";
std::string pattern = "ABC";

Salida esperada:
std::string expected = "BANC";

Entrada:
string text = "ADOBECODEBANC";
string pattern = "ABC";

Salida esperada:
string expected = "BANC";

Entrada:
text = "a"
pattern = "aa"

Salida esperada:
expected = ""

Entrada:
std::string text = "a";
std::string pattern = "aa";

Salida esperada:
std::string expected = "";

Entrada:
string text = "a";
string pattern = "aa";

Salida esperada:
string expected = "";

Referencias

Este reto está adaptado para CodeUtility. Sigue el enunciado y las restricciones indicadas arriba.

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