day 8 part 2 dp

inputs/day8.txt

@@ -0,0 +1,668 @@
+LRRLRRRLRRLLLRLLRRLRRLLRRRLRRLLRLRRRLRLRRLRLRRRLRLRLRRLLRLRLRRLRRRLRRRLRRRLRLRRLLLLRLLRLLRRLRRRLLLRLRRRLRLRRRLRLRRLRRRLRRRLRLRLLRRRLLRLLRLRLRLRLLRRLRRLRRRLRRLRLRLRLRLRRLRRRLLRRRLLRLLLRRRLLRRRLRRRLRRLRLRRLRLLRRLLRRLRLRLRRLRLRRLLRRRLLRRRLLRLRRRLRLRRRLRLRRRLRRRLRRLRRLRRLLRRRLRRRLLLRRRR
+
+RGT = (HDG, QJV)
+QDM = (GPB, SXG)
+DJN = (TQD, BQN)
+QGG = (GGS, PTC)
+FJP = (MPB, HFP)
+KNB = (QHC, XBQ)
+RGR = (LSQ, LJV)
+HDP = (RLT, LRK)
+DBQ = (KTM, MPJ)
+QSG = (QVF, QVF)
+JKR = (XTK, RQB)
+BJH = (VKC, SML)
+LRF = (NPJ, HKK)
+JRD = (BQX, LGK)
+HVD = (CJP, TLM)
+VCG = (JMS, RJB)
+PCT = (KJC, RCQ)
+DRK = (PTR, FSH)
+BJN = (GVD, XXN)
+CXL = (FMB, NKM)
+TVM = (TTX, RCG)
+PTP = (KQQ, XLR)
+CKX = (VKR, RDH)
+TCP = (TPX, BSB)
+KSC = (JFL, CHL)
+DTF = (BTQ, TTQ)
+GFQ = (HKK, NPJ)
+BKD = (CXB, JSB)
+DJB = (TMG, DDQ)
+CQV = (SSX, DFT)
+BPC = (KNR, CGF)
+KLT = (BMF, XQC)
+NLB = (DBD, VCL)
+HJS = (FXK, FLB)
+PSL = (PBC, XFX)
+LVL = (JFD, RJD)
+JMX = (CGG, RRL)
+TTQ = (XVC, RCT)
+NLG = (FXK, FLB)
+LCD = (JSB, CXB)
+HVR = (CRV, HHM)
+HGV = (VCG, JDT)
+LND = (TTL, QCH)
+CSX = (DHS, JLB)
+BRJ = (BCT, XFS)
+XVN = (RDH, VKR)
+HQB = (BVD, GPC)
+PGP = (CFB, HQL)
+NFB = (BDX, JDK)
+HJK = (VVX, HTP)
+KKB = (NSF, GPP)
+JDV = (XJG, FDR)
+VGC = (HFV, JMT)
+BBG = (GTF, KTP)
+HTB = (BTC, KKC)
+KPL = (MXJ, MBN)
+NHD = (GCT, TGP)
+DMP = (KRH, SPM)
+LRB = (GNP, GGB)
+BGA = (MPB, HFP)
+PBZ = (KXQ, CKP)
+BQF = (LJC, VGC)
+KKC = (DJB, MCS)
+RRL = (QCK, RKN)
+PDZ = (RGF, BHL)
+SLA = (BCD, VJK)
+XRC = (SKL, VBP)
+HHM = (HSJ, NTR)
+BNP = (GPP, NSF)
+GHM = (HLC, KQK)
+LMV = (VTS, NFQ)
+QKF = (JNG, THN)
+PCG = (HSQ, DMP)
+CKG = (XSX, RDF)
+RMV = (FQL, HJL)
+LPG = (RJD, JFD)
+HFJ = (VQX, LQZ)
+QRF = (BCR, VSV)
+JSR = (BJJ, DVJ)
+TKS = (KTP, GTF)
+JNG = (DJD, XLM)
+XDG = (JKR, MRR)
+PFB = (QLT, PBD)
+NTR = (HBV, NRX)
+NMN = (BDX, JDK)
+MGP = (QMT, VLG)
+PTA = (LSP, TXX)
+CRK = (CJP, TLM)
+NVL = (STQ, QFH)
+VCL = (XFD, MGN)
+LJM = (VJH, NXV)
+GCJ = (RFS, QLN)
+NSF = (TKV, LKQ)
+PQN = (QHC, XBQ)
+GHK = (FNT, LCX)
+SFK = (FQL, HJL)
+FNX = (VXK, BJN)
+SSX = (MGK, KRX)
+FSH = (FNB, QFL)
+XFS = (BCK, CKG)
+VLQ = (XJV, HLM)
+JLB = (MMR, HMQ)
+GXX = (HLN, SGX)
+PKX = (QKF, SHQ)
+VND = (CDN, VVH)
+HJG = (FXR, VDR)
+GGR = (QRF, JMB)
+BQG = (CRV, HHM)
+RFS = (BHN, MNL)
+CSK = (DCX, VXG)
+RSL = (XCG, JGV)
+KRH = (CKX, XVN)
+VBP = (NLF, TVM)
+AAA = (MQQ, VHH)
+BVX = (LPG, LVL)
+QCG = (JKJ, CDR)
+JMQ = (HLR, GGT)
+NLF = (RCG, TTX)
+CXB = (NLG, HJS)
+VXG = (SDN, FCJ)
+XFT = (GNP, GGB)
+SST = (GGS, PTC)
+NNK = (PTD, HPF)
+RKN = (XVF, MMX)
+TGP = (SSN, MRT)
+TSR = (SFK, RMV)
+GBL = (NKQ, KVH)
+NKJ = (CGM, TCP)
+KVH = (VTK, GKV)
+VBB = (DXX, JVB)
+KGC = (HMK, TFL)
+PNL = (QLT, PBD)
+TNG = (QSG, TPL)
+HCV = (KVR, PKK)
+RBB = (TKG, CQK)
+BJJ = (GCN, PLQ)
+JRF = (DHC, XCQ)
+FLJ = (CKP, KXQ)
+KVR = (DJS, NKJ)
+HGT = (KVX, LTP)
+MGN = (JDS, LNS)
+FRC = (QLM, FHJ)
+MBN = (TRQ, MRD)
+TMG = (CTD, SFH)
+TNT = (JDG, HGV)
+DXP = (SSX, DFT)
+VVD = (JXJ, PGP)
+CHL = (XSL, SNZ)
+CGS = (GFQ, LRF)
+BHL = (FNQ, HFD)
+XHF = (NHD, PQC)
+PMH = (CNS, SVM)
+VKR = (TBT, TLT)
+LLK = (TQD, BQN)
+LVJ = (PDD, LML)
+JPB = (PRK, VCV)
+HSJ = (HBV, NRX)
+VJH = (DTL, BRL)
+SNJ = (DXP, CQV)
+HQL = (KDL, QFN)
+XHM = (HVG, ZZZ)
+RDX = (KTM, MPJ)
+MQQ = (LSC, DGG)
+TMM = (GMQ, RTL)
+JKP = (LRF, GFQ)
+TKG = (BDN, BDN)
+FBJ = (HLR, GGT)
+PTD = (LMV, QBR)
+FMB = (DQT, RRH)
+TTX = (LVJ, FXX)
+BXL = (BTQ, TTQ)
+QMV = (GND, FGG)
+HFD = (TBQ, VVD)
+NFQ = (PMH, DMM)
+RTH = (TPG, VDP)
+VHH = (DGG, LSC)
+HLN = (SPP, SPP)
+XQD = (PNL, PFB)
+GVD = (BPC, JJG)
+XRN = (DHJ, LBD)
+GNP = (NRC, NRC)
+JLC = (JHB, DRK)
+LGK = (BSK, BRV)
+BSB = (MBM, XHF)
+PBJ = (FRC, RFH)
+DRH = (VMR, XVK)
+RDF = (BHV, NGM)
+MMR = (HGD, PBJ)
+RGF = (HFD, FNQ)
+HTR = (RCQ, KJC)
+NGM = (FJP, LCZ)
+PJF = (QKF, SHQ)
+BCK = (XSX, XSX)
+PBD = (SXM, HTT)
+VCV = (GRD, VVT)
+TFL = (CCX, HQB)
+THT = (NXX, TSR)
+JMS = (RCF, XRC)
+FKG = (XRN, PHG)
+TBQ = (PGP, JXJ)
+SML = (TCH, DPF)
+RJB = (RCF, XRC)
+KJC = (LND, JNR)
+HPT = (DLM, MVH)
+NKM = (DQT, RRH)
+JSJ = (QFH, STQ)
+KJJ = (XXT, DBC)
+FGG = (HPT, GMM)
+RFH = (QLM, FHJ)
+TLM = (DKN, QGH)
+MJV = (QSG, TPL)
+DHG = (RGT, CVS)
+BVB = (QLJ, SNR)
+RMH = (JKR, MRR)
+XFX = (SNJ, QBD)
+LNS = (SFQ, GGR)
+QJV = (LRB, XFT)
+BHV = (FJP, FJP)
+JMT = (BJM, NPC)
+BDN = (JFL, JFL)
+CHC = (CXL, SXC)
+VBN = (VBB, CFM)
+SFQ = (QRF, JMB)
+XXN = (JJG, BPC)
+MCS = (TMG, DDQ)
+CFV = (DHG, NKS)
+FXK = (JSR, GLR)
+JMB = (VSV, BCR)
+VVT = (LST, GCJ)
+VRL = (DJN, LLK)
+XLB = (FGJ, PGB)
+JVC = (XXT, DBC)
+VQX = (BCD, VJK)
+DVJ = (GCN, PLQ)
+BTQ = (RCT, XVC)
+LCX = (JHK, KPL)
+FSD = (NNC, XLX)
+TSQ = (FKM, HFJ)
+HGD = (RFH, FRC)
+HJL = (JDV, LNV)
+FSB = (DBD, VCL)
+DCX = (SDN, FCJ)
+BHH = (JPK, GVQ)
+JHB = (PTR, FSH)
+THP = (SXC, CXL)
+LRK = (QCT, FPT)
+PTC = (LMF, DLF)
+DHS = (HMQ, MMR)
+GDK = (SNR, QLJ)
+CNJ = (JKJ, CDR)
+SBM = (BCT, XFS)
+GJP = (RJK, DDX)
+DFT = (KRX, MGK)
+XBQ = (BNP, KKB)
+FGJ = (VRL, CKV)
+QVF = (XTM, XTM)
+VJK = (BFB, CKT)
+VJX = (BKD, LCD)
+KQK = (GBL, HPK)
+KKX = (BDC, SKC)
+CRV = (HSJ, NTR)
+JNR = (QCH, TTL)
+HTG = (NQK, GJP)
+QLN = (MNL, BHN)
+GMB = (VVX, HTP)
+JDG = (JDT, VCG)
+QLT = (HTT, SXM)
+CLK = (VJB, SRH)
+GSX = (XKX, RSL)
+MQX = (RTH, LPL)
+ZZZ = (VHH, MQQ)
+PKK = (DJS, NKJ)
+MJT = (MQX, HTF)
+GLT = (TCD, HXV)
+PQX = (TGQ, JBF)
+VSX = (LTP, KVX)
+FSV = (FKG, NLC)
+FKR = (CQD, JPR)
+CKT = (RDX, DBQ)
+JFD = (TKS, BBG)
+CNM = (TBH, XRF)
+PBC = (SNJ, QBD)
+MRT = (QCG, CNJ)
+RCQ = (JNR, LND)
+JJG = (KNR, CGF)
+CFP = (JVT, GSX)
+BTG = (SBM, BRJ)
+BJM = (CRK, HVD)
+XVK = (CDS, BQF)
+BCT = (BCK, CKG)
+LST = (RFS, QLN)
+DNM = (VMR, XVK)
+GPB = (GNX, DJV)
+FDR = (FTG, LFQ)
+LCZ = (HFP, MPB)
+XJV = (FCP, JHV)
+HQC = (TRG, SCP)
+RMD = (QMV, NNH)
+SRH = (FLL, QKV)
+QBD = (CQV, DXP)
+RRH = (NCB, TSQ)
+XVF = (NFB, NMN)
+QMT = (GLT, NTS)
+GBX = (TKG, CQK)
+MFP = (TLH, QXD)
+XKG = (MHN, NLR)
+HQH = (HPF, PTD)
+LLR = (CNR, CRF)
+LSP = (SVQ, VJX)
+HSH = (LRK, RLT)
+TTL = (FKR, QMF)
+CFB = (KDL, QFN)
+SXG = (GNX, DJV)
+LTP = (KJJ, JVC)
+HSQ = (SPM, KRH)
+SHG = (DRH, DNM)
+DHJ = (QXR, GHK)
+GGK = (PRK, VCV)
+TRG = (PJN, CFV)
+TTF = (LJV, LSQ)
+VVH = (HSH, HDP)
+QXR = (FNT, LCX)
+DTL = (FSV, VQV)
+KVX = (JVC, KJJ)
+HLR = (BTG, MKN)
+XCG = (QTJ, HTQ)
+LML = (JMQ, FBJ)
+FMS = (XTM, VXJ)
+CTD = (JHQ, XLB)
+TCD = (CSK, GLS)
+MRR = (RQB, XTK)
+SSN = (CNJ, QCG)
+VLG = (NTS, GLT)
+JDT = (JMS, RJB)
+TPJ = (XFX, PBC)
+PDD = (FBJ, JMQ)
+QLJ = (NVL, JSJ)
+TVX = (JPB, GGK)
+QCT = (GBX, RBB)
+GMM = (DLM, MVH)
+RLT = (QCT, FPT)
+PFH = (HTG, DNF)
+DQN = (XCQ, DHC)
+XQC = (QJQ, JLC)
+QCH = (FKR, QMF)
+GMQ = (KPJ, RTF)
+HVJ = (QMV, NNH)
+VDP = (TVX, VFB)
+NXV = (DTL, BRL)
+JHK = (MXJ, MBN)
+JPK = (GQN, MFP)
+SSH = (KQK, HLC)
+FNB = (GPS, LLR)
+HTP = (SPG, CSX)
+HHN = (DNF, HTG)
+QJQ = (JHB, DRK)
+PFC = (KRJ, JLV)
+HFP = (JRD, MMT)
+HGC = (QCJ, CXG)
+KLG = (BVX, QSM)
+LHG = (HLM, XJV)
+CGG = (QCK, RKN)
+XVC = (CGS, JKP)
+FCJ = (TMM, MBL)
+KLC = (CDN, VVH)
+CRF = (LVG, FNX)
+PBP = (GSX, JVT)
+GLS = (DCX, VXG)
+DJD = (QGG, SST)
+BJV = (DMP, HSQ)
+MNL = (JSG, LNC)
+DNF = (NQK, GJP)
+NLR = (SSH, GHM)
+HSP = (JBF, TGQ)
+NRX = (DTX, CJK)
+VVX = (CSX, SPG)
+LSC = (DCL, QBB)
+VXJ = (FLJ, PBZ)
+CDR = (NXN, NMT)
+SGM = (NXV, VJH)
+XSX = (BHV, BHV)
+MGK = (FXG, XTG)
+VPC = (SKC, BDC)
+HBV = (CJK, DTX)
+RQB = (PCT, HTR)
+FXR = (HKP, LVP)
+BRL = (FSV, VQV)
+VXK = (GVD, XXN)
+SDN = (MBL, TMM)
+FCP = (HXD, SHG)
+XTG = (KLT, SPX)
+LBD = (GHK, QXR)
+JHQ = (FGJ, PGB)
+XXT = (KNB, PQN)
+VKC = (TCH, DPF)
+GQN = (QXD, TLH)
+HLM = (JHV, FCP)
+JDK = (TTF, RGR)
+VTS = (PMH, DMM)
+VMR = (CDS, BQF)
+XJA = (BHL, RGF)
+MMS = (NLR, MHN)
+DPF = (PQX, HSP)
+NNH = (FGG, GND)
+JSB = (NLG, HJS)
+XLR = (GMB, HJK)
+RCF = (VBP, SKL)
+JPD = (HTF, MQX)
+CJP = (DKN, QGH)
+BLC = (HGV, JDG)
+FTG = (PSL, TPJ)
+JDS = (SFQ, GGR)
+FQL = (JDV, LNV)
+JBF = (CHC, THP)
+HVG = (MQQ, VHH)
+LKQ = (NLX, HHX)
+KRX = (FXG, XTG)
+JNA = (CKP, KXQ)
+JPR = (CGD, BJH)
+CJK = (MSQ, HCV)
+QSM = (LVL, LPG)
+BQN = (PCG, BJV)
+SFH = (XLB, JHQ)
+XLD = (QNN, LVC)
+GTF = (HTB, RQV)
+BMF = (QJQ, JLC)
+THN = (XLM, DJD)
+VPB = (FXR, VDR)
+RQX = (XQD, JDL)
+LNV = (XJG, FDR)
+NXN = (DSS, KMF)
+QTJ = (DKR, KLG)
+VSV = (KHH, FSD)
+DBD = (MGN, XFD)
+DHC = (PHH, HQC)
+QGH = (VBN, DPJ)
+NTS = (TCD, HXV)
+BSK = (BQG, HVR)
+MRD = (VPB, HJG)
+BQX = (BSK, BRV)
+BRV = (BQG, HVR)
+SVM = (PKX, PJF)
+KRJ = (NMC, TBX)
+GTH = (HVG, HVG)
+SCP = (PJN, CFV)
+CGF = (VFD, GXX)
+SHQ = (THN, JNG)
+JVT = (XKX, RSL)
+RJK = (RVD, CLK)
+MKN = (SBM, BRJ)
+JHV = (HXD, SHG)
+TLT = (JRF, DQN)
+QBR = (NFQ, VTS)
+CNR = (FNX, LVG)
+LVG = (BJN, VXK)
+FCQ = (BHL, RGF)
+JXJ = (CFB, HQL)
+DJV = (BXL, DTF)
+DTX = (HCV, MSQ)
+JLV = (NMC, TBX)
+STQ = (RMH, XDG)
+NQK = (DDX, RJK)
+KTP = (RQV, HTB)
+RLP = (JDL, XQD)
+TQD = (PCG, BJV)
+GGT = (MKN, BTG)
+VJB = (FLL, QKV)
+JVB = (MJT, JPD)
+VQV = (FKG, NLC)
+FXG = (KLT, SPX)
+XFD = (LNS, JDS)
+NKS = (CVS, RGT)
+QFL = (GPS, LLR)
+CDN = (HSH, HDP)
+RTL = (RTF, KPJ)
+CCX = (GPC, BVD)
+CXG = (THT, VVN)
+GRC = (CGG, RRL)
+MXJ = (TRQ, MRD)
+SXM = (HQH, NNK)
+LJV = (SMP, VRJ)
+RJD = (TKS, BBG)
+HMQ = (PBJ, HGD)
+MSQ = (KVR, PKK)
+GPS = (CNR, CRF)
+FNT = (KPL, JHK)
+HDG = (LRB, XFT)
+LFQ = (PSL, TPJ)
+VFD = (HLN, SGX)
+SKC = (CFP, PBP)
+TKV = (HHX, NLX)
+GPP = (TKV, LKQ)
+JSG = (PFH, HHN)
+BCD = (CKT, BFB)
+MPJ = (HVJ, RMD)
+GCT = (MRT, SSN)
+XTM = (FLJ, FLJ)
+DKN = (DPJ, VBN)
+SVN = (VLG, QMT)
+LQZ = (VJK, BCD)
+PHS = (GPB, SXG)
+XCQ = (HQC, PHH)
+QNN = (FCQ, FCQ)
+DMM = (CNS, SVM)
+DBC = (PQN, KNB)
+JFL = (XSL, XSL)
+MBL = (RTL, GMQ)
+VTK = (MGP, SVN)
+SKL = (TVM, NLF)
+HXD = (DRH, DNM)
+GNX = (DTF, BXL)
+XLM = (SST, QGG)
+QMF = (CQD, JPR)
+HMK = (HQB, CCX)
+MMT = (BQX, LGK)
+PJN = (DHG, NKS)
+DGG = (DCL, QBB)
+SPX = (XQC, BMF)
+MHN = (SSH, GHM)
+RDH = (TLT, TBT)
+NMC = (KKX, VPC)
+GKV = (SVN, MGP)
+XSL = (LSP, TXX)
+TGQ = (THP, CHC)
+TRQ = (HJG, VPB)
+VHK = (KRJ, JLV)
+TPX = (MBM, XHF)
+QXD = (QDM, PHS)
+VRJ = (GDK, BVB)
+KXQ = (RLP, RQX)
+CNS = (PKX, PJF)
+TPG = (TVX, VFB)
+PTR = (QFL, FNB)
+QHC = (KKB, BNP)
+CDS = (VGC, LJC)
+BTC = (MCS, DJB)
+NLC = (PHG, XRN)
+BDC = (CFP, PBP)
+FPT = (GBX, RBB)
+CQD = (BJH, CGD)
+XKX = (JGV, XCG)
+TXX = (VJX, SVQ)
+SPP = (GTH, GTH)
+KTM = (HVJ, RMD)
+JGV = (HTQ, QTJ)
+HKP = (KLC, VND)
+GLR = (DVJ, BJJ)
+LMF = (LHG, VLQ)
+CLG = (TFL, HMK)
+KHH = (NNC, XLX)
+HTQ = (KLG, DKR)
+QFN = (CNM, TCT)
+FLL = (TNG, MJV)
+HFV = (NPC, BJM)
+NPC = (HVD, CRK)
+HKK = (KGC, CLG)
+XRF = (PFC, VHK)
+GGS = (DLF, LMF)
+LVC = (FCQ, PDZ)
+DXX = (MJT, JPD)
+DCL = (HGT, VSX)
+LNC = (HHN, PFH)
+TBT = (JRF, DQN)
+DKR = (QSM, BVX)
+KNL = (QCJ, CXG)
+TLH = (PHS, QDM)
+NMT = (DSS, KMF)
+HLC = (GBL, HPK)
+BDX = (TTF, RGR)
+HXV = (GLS, CSK)
+TBH = (VHK, PFC)
+QBB = (HGT, VSX)
+TCH = (PQX, HSP)
+QFH = (XDG, RMH)
+GND = (HPT, GMM)
+CVS = (QJV, HDG)
+FNQ = (VVD, TBQ)
+NCB = (FKM, FKM)
+FHJ = (MMS, XKG)
+VFB = (GGK, JPB)
+RQV = (KKC, BTC)
+NLX = (KNL, HGC)
+TCT = (XRF, TBH)
+GGB = (NRC, XLD)
+JKJ = (NXN, NMT)
+SPG = (DHS, JLB)
+LVP = (VND, KLC)
+NPJ = (KGC, CLG)
+RVD = (SRH, VJB)
+HTT = (NNK, HQH)
+PQC = (TGP, GCT)
+MPB = (MMT, JRD)
+BCR = (FSD, KHH)
+BHN = (LNC, JSG)
+SMP = (BVB, GDK)
+GPC = (NLB, FSB)
+NMD = (GTH, XHM)
+CGD = (SML, VKC)
+CKP = (RQX, RLP)
+DQT = (NCB, NCB)
+KDL = (CNM, TCT)
+CQK = (BDN, KSC)
+NXX = (SFK, RMV)
+RTF = (LJM, SGM)
+KQQ = (HJK, GMB)
+KMF = (BVK, BHH)
+HPK = (KVH, NKQ)
+PLQ = (MLH, PTP)
+RCG = (LVJ, FXX)
+HPF = (LMV, QBR)
+TBX = (VPC, KKX)
+NKQ = (VTK, GKV)
+PRK = (GRD, VVT)
+TPL = (QVF, FMS)
+CFM = (DXX, JVB)
+SGX = (SPP, NMD)
+MLH = (KQQ, XLR)
+NNC = (TNT, BLC)
+XLX = (TNT, BLC)
+MBM = (NHD, PQC)
+PHH = (TRG, SCP)
+QKV = (TNG, MJV)
+XJG = (FTG, LFQ)
+QCK = (XVF, MMX)
+SVQ = (LCD, BKD)
+SXC = (FMB, NKM)
+RCT = (CGS, JKP)
+KNR = (VFD, GXX)
+FKM = (VQX, VQX)
+CKV = (DJN, LLK)
+DDX = (CLK, RVD)
+GCN = (PTP, MLH)
+BFB = (DBQ, RDX)
+SNZ = (TXX, LSP)
+MVH = (JMX, GRC)
+HHX = (HGC, KNL)
+GRD = (GCJ, LST)
+SPM = (CKX, XVN)
+LPL = (VDP, TPG)
+CGM = (BSB, TPX)
+FXX = (LML, PDD)
+PGB = (CKV, VRL)
+MMX = (NMN, NFB)
+DJS = (TCP, CGM)
+HTF = (LPL, RTH)
+DSS = (BVK, BHH)
+KPJ = (SGM, LJM)
+DLM = (GRC, JMX)
+LSQ = (SMP, VRJ)
+SNR = (NVL, JSJ)
+DPJ = (CFM, VBB)
+DDQ = (SFH, CTD)
+VVN = (NXX, TSR)
+QLM = (XKG, MMS)
+QCJ = (VVN, THT)
+JDL = (PFB, PNL)
+DLF = (LHG, VLQ)
+LJC = (JMT, HFV)
+GVQ = (GQN, MFP)
+XTK = (HTR, PCT)
+NRC = (QNN, QNN)
+PHG = (DHJ, LBD)
+BVD = (NLB, FSB)
+VDR = (HKP, LVP)
+BVK = (GVQ, JPK)
+FLB = (JSR, GLR)

src/bin/day8.rs

@@ -0,0 +1,218 @@
+#![forbid(elided_lifetimes_in_paths, unsafe_code)]
+
+use aoc23::read;
+use chumsky::prelude::*;
+use std::collections::{HashMap, HashSet, VecDeque};
+
+enum Instruction {
+	Left,
+	Right
+}
+
+impl Instruction {
+	fn parser() -> impl Parser<char, Self, Error = Simple<char>> {
+		choice((
+			just('L').map(|_| Self::Left),
+			just('R').map(|_| Self::Right)
+		))
+	}
+}
+
+#[derive(Debug)]
+struct Node {
+	left: String,
+	right: String
+}
+
+fn parse_node_name() -> impl Parser<char, String, Error = Simple<char>> {
+	none_of([',', ')', ' '])
+		.repeated()
+		.at_least(1)
+		.map(|chars| chars.into_iter().collect())
+}
+
+impl Node {
+	fn parser() -> impl Parser<char, Self, Error = Simple<char>> {
+		just("(")
+			.ignore_then(parse_node_name())
+			.then_ignore(just(", "))
+			.then(parse_node_name())
+			.then_ignore(just(")"))
+			.map(|(left, right)| Self { left, right })
+	}
+}
+
+#[derive(Debug)]
+struct Network {
+	nodes: HashMap<String, Node>
+}
+
+impl Network {
+	fn parser() -> impl Parser<char, Self, Error = Simple<char>> {
+		parse_node_name()
+			.then_ignore(just(" = "))
+			.then(Node::parser())
+			.then_ignore(just("\n"))
+			.repeated()
+			.map(|nodes| Self {
+				nodes: nodes.into_iter().collect()
+			})
+	}
+
+	fn node(&self, node: &str) -> &Node {
+		self.nodes
+			.get(node)
+			.unwrap_or_else(|| panic!("Failed to get node {node:?}"))
+	}
+
+	fn left(&self, node: &str) -> &str {
+		&self.node(node).left
+	}
+
+	fn right(&self, node: &str) -> &str {
+		&self.node(node).right
+	}
+}
+
+fn parser() -> impl Parser<char, (Vec<Instruction>, Network), Error = Simple<char>> {
+	Instruction::parser()
+		.repeated()
+		.at_least(1)
+		.then_ignore(just("\n\n"))
+		.then(Network::parser())
+		.then_ignore(end())
+}
+
+#[derive(Copy, Clone, Debug)]
+struct Ghost<'a> {
+	node: &'a str,
+	i: usize,
+	steps: u128
+}
+
+impl<'a> Ghost<'a> {
+	fn new(node: &'a str) -> Self {
+		Self {
+			node,
+			i: 0,
+			steps: 0
+		}
+	}
+
+	fn advance(&mut self, ghost: Ghost<'a>) {
+		self.node = ghost.node;
+		self.i = ghost.i;
+		self.steps += ghost.steps;
+	}
+}
+
+fn main() -> anyhow::Result<()> {
+	let (instructions, network) = read("inputs/day8.txt", parser())?;
+
+	// build a lookup map of left/right predecessors
+	let mut left_pred: HashMap<&str, Vec<&str>> = HashMap::new();
+	let mut right_pred: HashMap<&str, Vec<&str>> = HashMap::new();
+	for (node, next) in &network.nodes {
+		left_pred.entry(&next.left).or_default().push(node);
+		right_pred.entry(&next.right).or_default().push(node);
+	}
+	eprintln!("Built pred lookup map");
+
+	// build a lookup map from instruction position and node with the length to the next
+	// finish node
+	let mut dp: HashMap<(&str, usize), Ghost<'_>> = HashMap::new();
+	let mut q: VecDeque<(&str, usize)> = VecDeque::new();
+	for node in network
+		.nodes
+		.keys()
+		.map(|node| node.as_str())
+		.filter(|node| node.ends_with('Z'))
+	{
+		for i in 0 .. instructions.len() {
+			dp.insert((node, i), Ghost { node, i, steps: 0 });
+			q.push_back((node, i));
+		}
+	}
+	while let Some((node, i)) = q.pop_front() {
+		let ghost = dp[&(node, i)];
+		let i_pred = match i {
+			0 => instructions.len() - 1,
+			i => i - 1
+		};
+		let pred = match instructions[i_pred] {
+			Instruction::Left => left_pred.get(node),
+			Instruction::Right => right_pred.get(node)
+		};
+		for node_pred in pred.into_iter().flatten() {
+			let new = (*node_pred, i_pred);
+			#[allow(clippy::map_entry)] // lint is opinionated garbage
+			if !dp.contains_key(&new) {
+				dp.insert(new, Ghost {
+					node: ghost.node,
+					i: ghost.i,
+					steps: ghost.steps + 1
+				});
+				q.push_back(new);
+				if dp.len() % 1_000_000 == 0 {
+					dbg!(dp.len());
+				}
+			}
+		}
+		if ghost.steps == 0 {
+			dp.remove(&(node, i));
+		}
+	}
+	eprintln!("Built ghost lookup map");
+	// for (key, value) in &dp {
+	// eprintln!("\t{key:?}\t = \t{value:?}");
+	// }
+
+	// let mut curr_node = "AAA";
+	// let mut i = 0;
+	// let mut steps = 0_u128;
+	// while curr_node != "ZZZ" {
+	// 	curr_node = match instructions[i] {
+	// 		Instruction::Left => network.left(curr_node),
+	// 		Instruction::Right => network.right(curr_node)
+	// 	};
+	// 	i = (i + 1) % instructions.len();
+	// 	steps += 1;
+	// }
+	// println!("{steps}");
+
+	let mut ghosts: Vec<Ghost<'_>> = network
+		.nodes
+		.keys()
+		.filter(|node| node.ends_with('A'))
+		.map(|node| Ghost::new(node))
+		.collect();
+	let mut progress = 0;
+	loop {
+		if ghosts[0].steps > 0
+			&& ghosts
+				.iter()
+				.skip(1)
+				.all(|ghost| ghost.steps == ghosts[0].steps)
+		{
+			println!("{}", ghosts[0].steps);
+			break;
+		}
+
+		let (ghost_index, ghost) = ghosts
+			.iter()
+			.enumerate()
+			.min_by_key(|(_, ghost)| ghost.steps)
+			.unwrap();
+		if ghost.steps - progress >= 1_000_000_000_000 {
+			progress = ghost.steps;
+			eprintln!("progress: {progress}");
+		}
+
+		// eprint!("{ghost:?}\t -> \t");
+		let ghost = dp[&(ghost.node, ghost.i)];
+		// eprintln!("{ghost:?}");
+		ghosts[ghost_index].advance(ghost);
+	}
+
+	Ok(())
+}