CREATE TABLE table_78849 ("Main contestant" TEXT, "Co-contestant  ( Yaar vs. Pyaar ) " TEXT, "Date performed" TEXT, "Scores by each individual judge" TEXT, "Total score/week" TEXT, "Position" TEXT, "Status" TEXT)

Who is the co-contestant (yaar vs. Pyaar) with Vishal Singh as the main contestant?
SELECT "Co-contestant (Yaar vs. Pyaar)" FROM table_78849 WHERE "Main contestant" = 'vishal singh'
SELECT "Co-contestant (Yaar vs. Pyaar)" FROM "table_78849" WHERE "Main contestant" = 'vishal singh'