Which men's singles has a women's singles of marketa koudelková as well as a Men's doubles of jan lanik / pavel weigner??
CREATE TABLE "junior_champions" (
  "year" real,
  "men_s_singles" text,
  "women_s_singles" text,
  "men_s_doubles" text,
  "women_s_doubles" text,
  "mixed_doubles" text
);
SELECT "men_s_singles" FROM "junior_champions" WHERE "women_s_singles"='marketa koudelková' AND "men_s_doubles"='jan lanik / pavel weigner';