user: Question: Who won mens singles the year Sveinn Logi Sölvason Tryggvi Nilsen won mens doubles and Elsa Nielsen won womens singles
Columns: ['Year', 'Mens singles', 'Womens singles', 'Mens doubles', 'Womens doubles', 'Mixed doubles']
Types: ['real', 'text', 'text', 'text', 'text', 'text']
Sample row: [1949.0, 'Einar Jónsson', 'no competition', 'Friðrik Sigurbjörnsson Guðjón Einarsson', 'no competition', 'no competition']
SQL:

assistant: SELECT "Mens singles" FROM "Table" WHERE "Mens doubles" = 'Sveinn Logi Sölvason Tryggvi Nilsen' AND "Womens singles" = 'Elsa Nielsen';