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Dendrochronology

Statement
Determine the age of a tree by counting the number of rings in a horizontal cross-section of its trunk. You are presented with a 10×[[N]] grid representing a cross-section of a tree. Every year, the tree <<alternates between a phase of rapid and slow growth>> depending on the season. To compute the age of the tree, count the <<number of transitions>> between a cycle of rapid grow (line of [[0]]), and slow growth (a line of [[1]]). <<A few considerations:>> - There is an arbitrary number of lines per cycle. - The tree trunk is not perfect and you <<must>> expect to see errors (i.e a [[0]] instead of [[1]] or vice-versa) or unwanted particles (represented by any other printable character). - However, on any given line there will always be <<10 characters>>, and <<less errors than valid characters>>. <<Here is an example:>> ```0000001000 1111111111 111111?111 0000000000```The age of this tree is <<2>> years since there are <<2>> transitions.

Input description
<<Line 1:>> An integer [[N]] representing the height of the grid <<Next [[N]] lines:>> Lines of 10 characters representing a section of the tree trunk

Output description
An integer representing the age of the tree

Constraints
0 < [[N]] ≤ 1000

Game modes
FastestShortest

Test cases
Simple case Test
Input
2 0000000000 1111111111
Output
1

Validator 1 Validator
Input
2 1111111111 0000000000
Output
1

Variable length Test
Input
5 0000000000 0000000000 0000000000 1111111111 1111111111
Output
1

Validator 2 Validator
Input
5 0000000000 0000000000 1111111111 1111111111 1111111111
Output
1

Errors Test
Input
8 1000000000 1000000000 1111111110 0111111111 1111000000 0000001111 1111111111 1000000000
Output
4

Validator 3 Validator
Input
8 1111000000 0000001111 1111111110 0111111111 0000000001 1000000000 1111111111 1111000000
Output
4

More Errors Test
Input
6 #000000000 000000000# 1101110111 00000!0000 0000000000 111111111#
Output
3

Validator 4 Validator
Input
8 L000000000 110000000L 1111111111 00000!0000 %000000000 1L1111111# ####000000 0000000!!!
Output
4

Very dirty trunk Test
Input
9 ####000000 !0!0!0!000 1111111111 AZER111111 QWER111111 000000LKLZ Y1Y1Y1Y111 1111000000 1111111111
Output
5

Validator 5 Validator
Input
9 1111111111 ;;;;000000 WXYZ111111 ABCD111111 000000LYLY N1N1N1N111 1111000000 1111111111 K0K0K0K000
Output
7

Very old tree Test
Input
603 *111111111 111*111111 21V11+1111 111116111Y 1111111111 100U0I0*01 1000&00001 1111SN1111 1111111111 11S1\11O1Q 000))#000D 00000,0P00 000000%000 1111211111 000000000E 0000000000 00000V0000 000000#002 111(#11),1 161111111# 1111,1111Z 11111111*1 1111111111 00H0500000 0I00804000 000UV000X0 0C0$0,0I00 1111111111 11191'1111 0000000&00 000000000& O0000M00O0 Z1B11211-1 1111111111 1111000000 11!111W11R 1111-1N111 1111111111 1111111111 0000000000 0000000000 &00000A00/ Y000000000 1111!"1G11 1111>11111 1111111M11 0000000000 0000000000 00000C!000 11R1111111 111EL91111 91T1(11U11 1?11+11&11 00$000000# 000W000NV0 11?112&111 1111111111 Z11P11C'11 1;11111111 111.=11B11 0000[A1000 00*:0\X000 000\00"000 1[11111111 1N1111<191 0000000000 1111I-S1U1 111111)111 1111111111 1#11"111@1 000000000> Q0;000Q00R :Q11111%11 N111211H:1 W11M11:111 1-11X%111X 0Z0,,00$00 00OW000A0@ "000B0000V 0000000000 1L1111'111 B11;11:.11 111"11U1U' ("000000V, 0000000000 00000000/0 0000000000 L000000000 11111R11)[ 11[01111=1 11110111ZQ 11&1111111 0000000000 1V1K111121 F11111=&41 111111X121 0220O00J00 1000000000 000T000000 00000000!0 000Y0100$0 114,11E1%1 000000A000 00C0000000 <00,W0000L 00000000K0 1(11511+1C 000!0000W0 0NK000000I 0000000000 0.00000)S0 1111111111 1Y11111111 111)11111S 0000000000 0000000000 500000+000 000+0X=00P 1111111111 1111Y11#31 N(1111Q311 0000-00K00 100L0L000J 11111111U1 +112111111 0000000000 0000000000 000000Y0D0 111111O111 11111C)111 1111111V11 0000%00000 ,000000L0N 0Z00000000 0000000000 1111T11111 1111111111 00"0000000 008000\0## 0082005003 05L00N0000 1111111111 11@51111R1 1111111111 >!00000000 -00D00'0K0 00>0000000 11111#11Z9 000K;W000X 0000000S00 0000000000 11R1UZ111R 1111111111 00W0N00000 000[000000 000?0000A0 00000000X0 11!O111S11 1111=1K/11 11$1111111 000V000A00 0600000F&0 0000000000 0000G00000 000,000000 11B16U1111 11>!1111MT 1N11111101 111!111111 111G11111D 0B00000070 1111$11H11 51O1131111 0'Z(000000 000000000+ *0H0600'00 0000000000 1111111111 61111111A1 11U1111%11 1111111111 1111111111 0,00N0000> 0000\BE000 0!0000000G )111611111 :11111A@1: 0000000000 0000D(00-0 008000$000 1/111K1BI1 111A111111 1N1111111W 0E000F000G 000000:)00 00\0900:00 0000000000 1111111T1! 1111011111 1F3181\111 11MP111>I1 0000000000 0400000<05 0000000000 11111?1111 11+114)111 11111E1111 1111111111 1!1/1I1111 0000000000 000&000000 11111111P1 111U111111 S00Z00000# 0000000000 0000000000 J11\1%11B1 S1(111V11% 111111H111 N0"U000000 0000000000 1711#1-11R A11V1111[P 00E00,S000 0000T00000 0020008001 1111D*5111 0000000000 0000000000 Y9000)000+ 11$11111V" 1[111<11'1 1E1111X1U> 1111=$1E[1 00000>0000 0000000000 ?00300000) 0N02000900 300000/000 *111111111 1(G111111S 1151111111 1+11111111 $000"00000 05:00M0[00 N000000030 0000000000 0000000000 1111111Q11 111111[A.1 G1111L13$1 1111111?11 00000@0000 00Z00[0!#0 0000>00000 0000000020 L00000T000 1511111!11 11W1111F11 0000000000 0000000*00 0000000000 111:1N1111 1111'11111 111@111111 00%000!000 0000000000 0H'0000000 CN00000000 11#1111111 1111111112 1:Z161Z111 N1111111Z1 M11Z1C1111 0=09000000 60#00000&D ;111111111 0000000000 S0000;09/0 0S0<N00000 0:00:000DT 000000$00< 111111D111 040:0X0000 0U0DO00000 HU000000V0 1111111111 W00000/00@ 0O00R0W00G 000A80!000 000000A00H 0700005000 1111111111 00E00.0000 11#1111111 0000000029 000000000/ Y0000003-0 000000*008 111111111L 111111G")1 1<111'11=1 0000000000 3A0000000# 0000000000 000%00I004 11111/1111 1111111111 1111111111 O1111T=11$ 0@)0R00>00 00000000\0 0000000+Z0 000000T000 00000000(0 E113111*1V 111DQ111;# /00000[000 00000Y0000 0000000000 1J%111S11V 111<191111 G1C1+E1111 1111111111 UD00000JY0 4000U0E00N 00000000B0 1:1111&\11 1111111211 11111111Z1 11:11111/1 00\0000M00 0000000000 000000000> 1111111111 115111-1O+ 1111311111 11DL&%1111 0000000000 08000QR0.0 000"000000 0000000000 0070000P&M 1111111111 1111111116 0000000000 000V000F00 00000000.5 0000000000 0000000000 21(811,111 000000R+00 111N111111 11T1(11$11 1:11111J1B 1111\11111 1111<11"11 0000000000 1111%1(:11 1111111111 1111111S1Z 111*111111 [D1111)111 0>00000X0K 0000000000 00000000N0 !'0000;000 00B0000X00 1@1111M111 1111115111 T111111;11 11111:118( 1*11111111 0000<X00(0 \0W00(0P00 1111111111 6E?11111D1 1*>11$6111 111511X111 1111O"1111 000000ET./ 0L\0000000 10711B1&11 <000002000 000&000000 0000000000 00U000Z00N 00%00$00;6 113?)11131 1181111111 1A1(11%111 11111!1111 X121211151 0000000000 0000000000 0000R@2000 00.0000000 00&00R(00E 1MN1111G12 0000100+0* 000K400%00 1111111611 11;+11+411 1141111111 111111.111 ,1(1111111 V000000000 0000000@Q0 0000000000 0000000(00 1111-11111 B11,111UN1 1111111111 $0$100000& 006&000000 000%00>"0" G0000000B0 1111:/1?11 WS111111.U 117,111111 11111/1111 0000000000 ).0800%000 000C(0=000 11W@111111 1111111111 1*1111111I IX1H11111= 1111131111 00(0?I0003 Z1F1111I21 1111111111 111H111111 (00Y0V0$00 0V00[0<500 00*00!D600 0000Y00$00 000000000I /E11?1$111 0#0?000C00 00%20!0000 11111111C1 11WR11N1=1 11N11B111$ 1"1111E1U1 11411111*1 0000000000 0LE0000&00 000FN00000 1P1111,11Y M111113911 H11111JJ<1 05000M0000 L000200000 11H11/-111 11118112*1 -11111111" 11Y1=E111% 111FA111U\ 0000000000 0000000400 000:000000 00U/00\K00 000000M0;0 111E111111 1.11111811 111N111111 000M0T000T >Q00V00000 0000000000 07000F0&0: 000900000& 1I11N11E19 ;1111111Z7 1111111111 1111711111 0C0000H000 0000000000 #O0000000< 1111111111 311131W111 1111111L11 151118111$ 000000[000 00000000)0 0000000000 0000080.00 1M11B$1111 #111111111 1S21111711 07\0000000 D000004000 %0H00Z0#00 E11111+1UJ P411111111 11K<111111 111K111111 1111111111 00>0000000 0(00000000 00000000\0 000K00L000 000&<00000 111X.11>"1 1111111111 1111SA1111 11W111111S 000000000. 1111111111 1117X1'111 00$8/00000 0000000000 11111111M4 11>11L;111 000000.M0% 000-0000W0 000004B0P0 0000000000 0000000000 1111111111 1111111111 0'000?00G0 0=00000000 0000000000 11111111E1 1171111111 11@K111111 111111111( 11I1111-11 V00000S)X0 0000P00000 1111111111 0000=0000E 0000000000 00Y00K000F 0@000000Q$ 000)000000 1111111111 U0000C>0X0 000000000X 0T0000/"00 ?000000000 1111111111 111111S1$1 000)00%008 511E11111' 111111-1(1 1T111,1311 000T40900B 0!0XO00S00 1111111111 1111111111 111114C1&? 11$11:11%1 :000000000 111111H1U1 1111M1111) 11"1L11LC1 1111111111 /0000::002 D1111111J1 11151=1011 1111111)11 T111111-11 1111111111 00L0000000 000P$DO000 0000000000 11111Y1C43 &1211Q11B1 111D11F111 1111111111 020+00;000 707000E0)0 0000X000:> 000#00000\ "1111WG611 %Q11111111 111L11111L 1111111111 0700E%F000 0000000S%% 00+000000> 0000000000 11111111W1 1#11111111 1182111+01 0000000000 000000I06P 0000070000 0000000000 1111P111D1 1AW18K1111 1111111111 1?11111111 08+0S0K000 000K000000 G000000000 000YJ00000 1)11111111 000000Y000 00000000O0 00B00000X0
Output
189

Validator 6 Validator
Input
602 0111111111 0000000$00 11111O1(11 300600[060 &9OD000000 "00O0000EW 000000U000 1111111111 1M111:11FQ ?00)0S0000 000000[0>0 0000!0E000 0:0S000000 C11'11[11O 1111111111 111/V111M2 0000000000 0000000000 0000000000 0200001.0) 11\1111111 1111111<11 1111000000 11H1111J+W 1@11311111 6111=11JO1 0(00>0$000 00000%0000 1N11111111 1111111111 000000000X 0IH0(000T0 [000000I09 1111111N1[ 11$1111111 11111111Z1 111C0D111# >,S111111. S100000011 1111111111 1F@111:11T 11111111T1 11111111<1 0000000000 07O0B00000 00000<00G0 0080006000 0000000000 1?11[11111 5000000000 0000000000 0J00000000 11=1111111 11111<1111 11111JZ11I 1111111111 11M11Z1KM1 0000000000 0000000000 000#H)000Z 11111311,1 0000M?0000 0000000000 11111-1111 111111E111 11N1111111 11;7111"10 #1111X1111 0000000000 03K00H=000 11<L11[111 1111O11V1; +)[111111! 000JI00#L0 0000000000 W0!0000400 000000000< 000000000/ 1311111111 Z1[611111) 11111111Y1 1111111111 1S111\S171 0[00(000N0 0:00000000 1111111E1R 111W11M111 11=7111!1, 0000000000 0000400000 00'0000I:/ 00@0000000 ,111111,18 111157'111 1111111111 &111711811 @O1111*111 0C00000000 000Z000000 000800$$0; 0000000000 111%-*1111 R111111111 0000000000 00Z#00>000 $000K0$040 00A0000000 1111111111 111111111[ 1T1111"11Y 0V00000000 0000000000 0;0L00040Q 0000000.00 11111B11:K 1111111111 1111111111 1+'11G1A11 11$111211M 0000000000 $00700080! 1111111"\1 0000000000 0000010000 00000M0JG! 1111[1''10 111-T11111 1111111111 11161:1UU1 1111111161 0000000000 S0000000/0 0000000000 Z0#0000=00 M111111111 11111%1111 0000000000 0000000004 0=000%00V0 1111111111 1111111111 1111111111 111111W111 1111111111 0000000000 00000#0000 000L0000ZM 1W1+11J111 1111111111 1111111111 111'118161 OX00000\Y0 0000+000A, 00E0000=00 000000!00, K11=111111 115%111111 2111?1111L 1111"11111 1111R11111 0T>00800?0 V*80000000 1111111:M8 11111111V1 11111=111M 1>1J1.1211 1111111111 000000!0B0 11E51111,1 1111111111 111111111( 111Z1#Y111 0000000000 0709000"00 11$11=1111 11111111)$ 1111111111 1111111111 11041111/1 000F000000 00K0000600 0000000Z00 116Y1L11/1 111111HD+1 11=1111P15 11=1(R1111 .!00000<00 11I1111111 1111W1=711 1111111111 11A1111+11 00;00<000S 000000+000 400+[0000A 0H00900000 0040000000 11111111H1 1111111111 B1111)@114 00000000)0 #20P000D00 00S0000IQ0 1111111111 111111(1K1 1111111111 0(0+0000.# 0000&0D090 0000000000 0000000000 1111>11111 1!1111111Q 1111111117 0000000000 0000000000 0000000000 0000000000 1111.211)1 0000009;0: 1;1Z1H#111 011Z111;11 1211J111U1 ,1111IKV11 0000020000 0000000000 0[>000'000 0000000Z00 1";1111"1. 1111111111 111;1M11&Y 191112115G 1111111B11 0<C000-Q00 (00(0000O0 0000000000 08000#<:00 11.1"11111 2111111111 1111111111 0000000000 7111111111 1(1)111111 0060000000 0000000M0W 00000W00O0 0$@0D00000 0000E09000 Z11:111111 0000000000 1111111111 0[000'0070 EY0J00000! 00(0000000 00000<0000 000030000' 1115Z%1111 0000000000 0000000000 1)<11=111P C1111111Y1 00000T0000 0-000!0000 0000000000 /00000300N \00000000I 11M11V1Q17 111G1&1,A1 11W*111Z13 *P0000000K 0000000R00 <000000-00 %1114111\1 1111111111 000000000G 1111O#1111 111;141111 J>00000000 0000000000 0000000000 00$0W00E0D 00000P0Y00 1111F11?1! 00'0008V0E 000N0?0000 (0000G0000 0000@0000\ 00[[00FG00 11"1-11Y11 Z111111311 0E*0&0D000 11111*11V1 1110111111 1R11""1111 0000000000 0000000Z00 0000000000 0000<00100 00Y0000S00 1P1111O111 %611((1111 1111111111 X11;111111 0000Z[90Q0 0900000000 11111F1111 000$0:0000 F0,0B000N0 050<00\00Q 11111111+= 1111111111 8J1111*111 1111111111 0000000000 0K700000)8 1111111111 1M1T111117 1111111111 0000000000 0#00000G00 11111!1111 1111111R11 11S1111N1Q 111H111111 000B00?000 000000-D00 0000000000 0\0\0000H0 0Z(00000&0 1111111111 1111(11111 1111111111 11U111111+ 0U00*00(:0 0000000000 0000000000 11(.Q111+1 1<111111;1 11H1111111 1111111C11 08000000Y/ 0'00007200 K111HW1111 1E1G111>11 4111111161 1111111111 0000000000 )0F0000000 0000000QV0 11111111X1 1111111111 000000W000 0000000000 000@000000 11H9111Z1) 1*11111111 0000000000 0000000000 111111\111 1111111111 1111111111 111L111111 G000P000-0 1111111111 1A1111111N 111*1S411D 111111=111 0000000000 008000I000 11T-11>11E 1N11111RC1 @1111111K1 1111111111 =11D11111J 0000000000 0000000000 0000D0.D/0 0000003000 11Z1111KH2 1111111111 1111G1L111 11111JU1=1 1T11911111 000AK00K0% .11111;11: 111111+111 /000X+:000 0000000000 00000000V0 000V0000UI 0080000000 11J1111111 0000000000 00.S%00000 0>0000FG00 0000000000 11);1"11Y1 O111111111 X1L1111191 00E=000000 90000000W0 000=00000, 5?00000000 1111111111 >000000;00 000+00C003 020600N0G0 11115111Q1 1111W11+11 1211*>1141 0000000000 00C000-000 00%00I000J 11111>11Y1 +7/111111T 0000000000 0O000Z0$0= 0000000800 111111G1,1 1111111111 11111-11+1 0000000000 H000000GC0 0020000000 0000000000 07"=000000 /111111111 11111G1311 ",000.F000 0000005(00 [<B11111=1 00L0000000 0000000000 I0000Z00:0 0-00<00S'0 11V1111111 1111111111 1111111.1P 005000;000 000$000000 0000000000 000000000P 1111111111 \111\)11U1 0L00000000 0@00&000Q0 00000"0000 0E0[0($000 0000000000 ?11&111111 D>0G0D0000 0000(00J(0 -00'000000 1111111111 111&1111P1 Y00040+I00 1111111I11 1(11?1>11* 1F11:111>1 1111111111 0%00Y000W0 010$0/00(0 0000000000 111111'111 0&40000000 0000000000 0I00#0000N S000000000 000000000Y 1111111!11 11111111A1 0000000000 811C111J11 +00H0*0000 O000000[0B 111A1T1111 000'0R&00J 0000000000 0-00000000 000%000000 111/1%[1V1 11NC1:1>11 1111W11111 1111111111 111111111G 0000Z00000 1111111111 1\11[11111 1111111111 R000000000 1111111111 11#1111111 11?1111111 1)11L11111 11T1111111 0000000300 0000000000 15111$1111 1+11111111 (111111111 1<1U1J1(11 0;000000T: 0009S00000 0000:000"0 VM0000000G 0000[+0+60 11W1111111 )11"WF1111 1M1D11?11[ 0000&$0Y00 0000005000 11111111Q1 '1.C111111 111111111? 111\7W111B 1111111111 (0000#S005 0000000000 D000000000 00P0500010 1111111111 111111F1E1 1111Q111#M 1111111111 11T1YZ1111 0000000000 1111111$11 00Y0@00000 '0D0000H00 1111111111 1111AW11HO 11101.111\ 000'0D00/0 000S0!00!1 000E00T00< 000;000000 Z111111111 000000000+ 0000YPI000 F00RD0"000 1111111111 1M11181131 G111181$11 1111[11111 0000V00000 111;1X1111 000D000000 1$1"!111H1 (5000C0000 111D11111B 111611!<1O 11%1111&&0 1!#1111@>1 1V11111111 00B0000000 000000000% A000M000T" 0000000000 :0(00>0000 1E115"D111 000L00000T 00000JU00W 00000000M0 0000000000 11=(1&11A1 111111111G 1111111111 0U00P0&000 00000,0A00 11%11W,111 00#&0N0000 0Z/000000: 0000000000 11111A1111 000H000000 Z0P000[0F0 0000000000 N+11111111 1>1111(1C1 1111111211 11111!1111 0000)0[008 0000000000 0000000000 0000000000 1111111111 1>111&;119 1141111.11 1'6+1K1111 0000000050 0S0*\00M00 01[000X0&0 000K00B000 1111113111 111/1#1111 N1111111F1 /E00P0000X 000.00:000 0040V30@00 0000000000 W00000000V 11<1R11111 1111111111 1111111111
Output
204

Trap Test
Input
12 1111111111 1111111111 1111111111 1111111111 1111111111 1111111111 1111111111 1111111111 1111111111 1111111111 1111111111 1111111111
Output
0

Validator 7 Validator
Input
16 0000000000 0000000000 0000000000 0000000000 0000000000 0000000000 0000000000 0000000000 0000000000 0000000000 0000000000 0000000000 0000000000 0000000000 0000000000 0000000000
Output
0

Solution language

Solution

Stub generator input
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