There are 100 small cards in the box, on which are written 1 to 100, randomly take out several small cards from the box, then calculate the sum of the numbers on these cards, and write the last two digits of the sum on a piece of paper. Place the new card in the box. After several such operations, there is one card left in the box. What is the number on this card?
盒子里有100张小卡片，上面分别写着1～100，从盒子里任意摸出若干张小卡片，然后算出这些卡片上各数的和，再将这个和的后面两位数写在一张新卡片上放入盒子里．经过若干次这样的操作后，盒子里还剩下一张卡片，这张卡片上的数是多少．
<result>50</result>