How many times will the clock(四位显示的电子钟) display three or more of the same number
|1 y& A7 q9 w k4 C+ B in a row over the course of one day?
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In case you were wondering ,the clock in this puzzle displays time on a 12-hour scale
! q( t2 K6 v. M) X$ Dnot on military time." a& y* R3 U' p4 [9 V$ C2 y5 C
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我是这样做的: / k/ T8 {* _' u7 n
aa:aa型 : 2种(00:00,11:11) : q& w v, T1 `* A/ K( A3 ?
aa:ab型 : 9*2种
f& v: t0 g6 D, laa:ba型 : 5*2种
" y" {2 _3 y- a( @ab:aa型 : 1+9种(当 a=1时 b不=2,因为在12小时的显示中,没有12:XX这样的时间显示)' W# H5 U4 I2 b7 ?
ba:aa型 : 5+1种
$ b; D3 B `0 q- N/ r4 q
. G" T! z& Z3 e( G' j总共46种 .考虑到a.m. p.m.总数*2=92种
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, m" \2 I- i" C/ i. b但答案不对 ,网上答案说是34种, 偶郁闷了~( m; b# N. i3 x/ G2 j$ d, `9 \9 i
4 d1 U: L2 @7 c: c" s1 L这个题到底怎么搞? |