The Arithmetic of Love(1987)

Machine tool fitter Ivan Mityushkin arrives to work in a small taiga village. After traveling through several cities and seeing a lot, the young man decides to drop anchor in a quiet harbor and live a quiet family life. Ivan falls in love with a young widow, Tatyana, and wants to marry her. Mityushkin manages to win over his beloved's six-year-old son and even befriends the boy. However, the woman is uncooperative. The fact is that Tatyana cannot forget her deceased husband, whom she loved dearly.