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##Challenge:

##Challenge rules:

##Step-by-step example:

##General rules:

##Test cases:

Challenge:

Challenge rules:

Step-by-step example:

General rules:

Test cases:

Output: An integer: the amount of times the list is riffle-shuffled. For a list, this means the list is split in two halves, and these halves are altered (i.e. riffle-shuffling the list [1,2,3,4,5,6,7,8,9,10] once would result in [1,6,2,7,3,8,4,9,5,10], so for this challenge the input [1,6,2,7,3,8,4,9,5,10] would result in 1).

Output: An integer: the amount of times the list is riffle-shuffled. For a list, this means the list is split in two halves, and these halves are interleaved (i.e. riffle-shuffling the list [1,2,3,4,5,6,7,8,9,10] once would result in [1,6,2,7,3,8,4,9,5,10], so for this challenge the input [1,6,2,7,3,8,4,9,5,10] would result in 1).

Input Output
[1,2,3] 0
[1,2,3,4,5] 0
[1,3,2] 1
[1,6,2,7,3,8,4,9,5,10] 1
[1,8,6,4,2,9,7,5,3,10] 2
[1,9,8,7,6,5,4,3,2,10] 3
[1,5,9,4,8,3,7,2,6,10] 4
[1,3,5,7,9,2,4,6,8] 5
[1,10,19,9,18,8,17,7,16,6,15,5,14,4,13,3,12,2,11,20] 10
[1,3,5,7,9,11,13,15,17,19,2,4,6,8,10,12,14,16,18,20] 17
[1,141,32,172,63,203,94,234,125,16,156,47,187,78,218,109,249,140,31,171,62,202,93,233,124,15,155,46,186,77,217,108,248,139,30,170,61,201,92,232,123,14,154,45,185,76,216,107,247,138,29,169,60,200,91,231,122,13,153,44,184,75,215,106,246,137,28,168,59,199,90,230,121,12,152,43,183,74,214,105,245,136,27,167,58,198,89,229,120,11,151,42,182,73,213,104,244,135,26,166,57,197,88,228,119,10,150,41,181,72,212,103,243,134,25,165,56,196,87,227,118,9,149,40,180,71,211,102,242,133,24,164,55,195,86,226,117,8,148,39,179,70,210,101,241,132,23,163,54,194,85,225,116,7,147,38,178,69,209,100,240,131,22,162,53,193,84,224,115,6,146,37,177,68,208,99,239,130,21,161,52,192,83,223,114,5,145,36,176,67,207,98,238,129,20,160,51,191,82,222,113,4,144,35,175,66,206,97,237,128,19,159,50,190,81,221,112,3,143,34,174,65,205,96,236,127,18,158,49,189,80,220,111,2,142,33,173,64,204,95,235,126,17,157,48,188,79,219,110,250]
 45

Input Output
[1,2,3] 0
[1,2,3,4,5] 0
[1,3,2] 1
[1,6,2,7,3,8,4,9,5,10] 1
[1,3,5,7,2,4,6] 2
[1,8,6,4,2,9,7,5,3,10] 2
[1,9,8,7,6,5,4,3,2,10] 3
[1,5,9,4,8,3,7,2,6,10] 4
[1,3,5,7,9,2,4,6,8] 5
[1,6,11,5,10,4,9,3,8,2,7] 6
[1,10,19,9,18,8,17,7,16,6,15,5,14,4,13,3,12,2,11,20] 10
[1,3,5,7,9,11,13,15,17,19,2,4,6,8,10,12,14,16,18,20] 17
[1,141,32,172,63,203,94,234,125,16,156,47,187,78,218,109,249,140,31,171,62,202,93,233,124,15,155,46,186,77,217,108,248,139,30,170,61,201,92,232,123,14,154,45,185,76,216,107,247,138,29,169,60,200,91,231,122,13,153,44,184,75,215,106,246,137,28,168,59,199,90,230,121,12,152,43,183,74,214,105,245,136,27,167,58,198,89,229,120,11,151,42,182,73,213,104,244,135,26,166,57,197,88,228,119,10,150,41,181,72,212,103,243,134,25,165,56,196,87,227,118,9,149,40,180,71,211,102,242,133,24,164,55,195,86,226,117,8,148,39,179,70,210,101,241,132,23,163,54,194,85,225,116,7,147,38,178,69,209,100,240,131,22,162,53,193,84,224,115,6,146,37,177,68,208,99,239,130,21,161,52,192,83,223,114,5,145,36,176,67,207,98,238,129,20,160,51,191,82,222,113,4,144,35,175,66,206,97,237,128,19,159,50,190,81,221,112,3,143,34,174,65,205,96,236,127,18,158,49,189,80,220,111,2,142,33,173,64,204,95,235,126,17,157,48,188,79,219,110,250]
 45