One Hundred Days After Childhood (1974)

Mitya (Boris Tokarev) is a young lad with a yen for the girl Lena (Tatiana Drubich). She, however, prefers the attentions of a fellow named Gleb (Yuri Agilin). After considerable rivalry and a fight or two, Mitya discovers that Sonya (Irina Malysheva), who returns his affection, is more his cup of tea.