from research import *
s=begin(1255,'Retain native Cainan in the kernel displacement field','Which existing comparison boundaries receive the native130 insertion?',{},['C1254','File18 §1.6','C1187'])
d=json.loads((ROOT/'model/regular_kernel_complete_staircase.json').read_text());j=d['labels'].index('Arphaxad');native=[x+(130 if i<=j else 0) for i,x in enumerate(d['field'])]
a=artifact('model/regular_kernel_native_staircase.json',json.dumps({'shared_boundary_labels':d['labels'],'matched_field':d['field'],'native_shared_boundary_field':native,'new_vertex':'nativeCainan itself is a separateLXX-labelled boundary betweenArphaxad andShelah','scope':'Insertion shiftsArphaxad andearlier; downstreamsharedrows stayfixed. No repeated+130 action.'},indent=2)+'\n')
finish(s,{'native_staircase':a,'native_head':native[0],'native_Arphaxad':native[j]},'Restoring nativeCainan raises the upstreamcomparison field by130, giving1380 atCreation and780 on theNoah/Shem/Arphaxad plateau. The downstreamsharedfield is unchanged, andCainan retains its ownnewvertex.','Reconstruct the separateeight-state placementfield fromT,C,S.',{'native_heads':native[0]==1380 and native[j]==780,'downstream_unchanged':native[j+1:]==d['field'][j+1:]})