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PROJECT EULER · #0790

Clock Grid

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There is a grid of length and width 50515093 points. A clock is placed on each grid point. The clocks are all analogue showing a single hour hand initially pointing at 12.

A sequence St is created where: S0=290797St=St12mod50515093t>0 The four numbers Nt=(S4t4,S4t3,S4t2,S4t1) represent a range within the grid, with the first pair of numbers representing the x-bounds and the second pair representing the y-bounds. For example, if Nt=(3,9,47,20), the range would be 3x9 and 20y47, and would include 196 clocks.

For each t (t>0), the clocks within the range represented by Nt are moved to the next hour 1212.

We define C(t) to be the sum of the hours that the clock hands are pointing to after timestep t.
You are given C(0)=30621295449583788, C(1)=30613048345941659, C(10)=21808930308198471 and C(100)=16190667393984172.

Find C(105).

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