Below is an context that describes a sql query, paired with an question that provides further information. Write an answer that appropriately completes the request.  # noqa: E501
### Context:
CREATE TABLE table_2518850_4 (year_of_previous_participation VARCHAR, total_number_of_participation VARCHAR, high_school_name VARCHAR)
### Question:
How many previous years did Maebashi Ikuei high school have a total number of 1 participation?
### Answer:
SELECT COUNT(year_of_previous_participation) FROM table_2518850_4 WHERE total_number_of_participation = 1 AND high_school_name = "Maebashi Ikuei"