编号为1-52张牌，正面向上，从第2张开始，以2为基数，是2的倍数的牌翻一次，直到最后一张牌；然后，从第3张开始，以3为基数，是3的倍数的牌翻一次，直到最后一张牌；然后…从第4张开始，以4为基数，是4的倍数的牌翻一次， 直到最后一张牌；...再依次5的倍数的牌翻一次，6的，7的直到以52为基数的翻过,输出：这时正面向上的牌；测试数据:52张牌

这时是正面的编号为:

　　1 4 9 16 25 36 49-1-52 number cards, face up, starting from 2 to 2 as the base, is a multiple of 2 cards turning once, until the last card　and then started from 3 to 3 as the base, is a multiple of 3 cards turning once, until the last card　and then ... start from 4 to 4 as the base, is a multiple of 4 cards turning once, until the last card　... then in turn 5 turn from multiple cards, 6, 7 to 52 as the base until the turn, the output: when the cards face up　test data: 52 cards, then a positive number: 14916253649