Odd number even number 〇 × check task 20×20 odd number even number 0 × check task 20×20_001 odd number even number 0 × check task 20×20_002 odd number even number 0 × check task 20×20_003 odd number even number 0 × check task 20×20_004 odd number even number 0 × check task 20×20_005 odd