#pragma GCC optimize("O3,unroll-loops")
#include <bits/stdc++.h>
using namespace std;
#define PB push_back
#define LL long long
#define int LL
#define FOR(i,a,b) for (int i = (a); i <= (b); i++)
#define FORD(i,a,b) for (int i = (a); i >= (b); i--)
#define REP(i,n) FOR(i,0,(int)(n)-1)
#define st first
#define nd second
#define ALL(x) (x).begin(), (x).end()
#define SZ(x) ((int)(x).size())
#define VI vector<int>
#define PII pair<int,int>
#define LD long double
struct fast_hash {
size_t operator()(int x) const {
x = ((x >> 16) ^ x) * 0x45d9f3b;
x = ((x >> 16) ^ x) * 0x45d9f3b;
x = (x >> 16) ^ x;
return x;
}
size_t operator()(const void* p) const {
return operator()((int)(intptr_t)p);
}
};
template<class K, class V>
struct HashMap : unordered_map<K, V, fast_hash> {
HashMap() { this->max_load_factor(0.25); }
};
struct HashSet : unordered_set<int, fast_hash> {
HashSet() { this->max_load_factor(0.25); }
};
template<class C> void mini(C& a4, C b4) { a4 = min(a4, b4); }
template<class C> void maxi(C& a4, C b4) { a4 = max(a4, b4); }
template<class L, class R> ostream &operator<<(ostream &os, pair<L,R> P) {
return os << "(" << P.st << "," << P.nd << ")";
}
template<class T> ostream &operator<<(ostream &os, vector<T> V){
os<<"[";for(auto vv:V)os<<vv<<",";return os<<"]";
}
template<class TH> void _dbg(const char *sdbg, TH h){cerr<<sdbg<<"="<<h<<"\n";}
template<class TH, class... TA> void _dbg(const char *sdbg, TH h, TA... a) {
while(*sdbg!=',')cerr<<*sdbg++;
cerr<<"="<<h<<","; _dbg(sdbg+1, a...);
}
#ifdef LOCAL
#define debug(...) _dbg(#__VA_ARGS__, __VA_ARGS__)
#else
#define debug(...) (__VA_ARGS__)
#define cerr if(0)cout
#endif
vector<VI> g;
VI get_code(const VI& lab) {
int n = SZ(g);
VI deg(n);
vector<bool> alive(n, true);
REP(v, n) deg[v] = SZ(g[v]);
priority_queue<PII, vector<PII>, greater<PII>> leaves;
REP(v, n) if (deg[v] == 1) leaves.push({lab[v], v});
VI code;
REP(step, n - 2) {
int leaf = -1;
while (SZ(leaves)) {
auto [lbl, v] = leaves.top();
leaves.pop();
if (!alive[v] || deg[v] != 1 || lab[v] != lbl) continue;
leaf = v;
break;
}
int par = -1;
for (int u : g[leaf]) if (alive[u]) {
par = u;
break;
}
code.PB(lab[par]);
alive[leaf] = false;
deg[leaf]--;
deg[par]--;
if (deg[par] == 1) leaves.push({lab[par], par});
}
return code;
}
VI solve() {
int n = SZ(g);
VI perm(n);
iota(ALL(perm), 1);
VI best;
bool has_best = false;
do {
VI code = get_code(perm);
if (!has_best || code < best) {
best = code;
has_best = true;
}
} while (next_permutation(ALL(perm)));
return best;
}
void print_ans(const VI& ans) {
REP(i, SZ(ans)) {
if (i) cout << ' ';
cout << ans[i];
}
cout << '\n';
}
signed main() {
ios_base::sync_with_stdio(0);
cin.tie(0);
int t;
cin >> t;
while (t--) {
int n;
cin >> n;
g.assign(n, {});
REP(i, n - 1) {
int a, b;
cin >> a >> b;
a--;
b--;
g[a].PB(b);
g[b].PB(a);
}
print_ans(solve());
}
return 0;
}
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 | #pragma GCC optimize("O3,unroll-loops") #include <bits/stdc++.h> using namespace std; #define PB push_back #define LL long long #define int LL #define FOR(i,a,b) for (int i = (a); i <= (b); i++) #define FORD(i,a,b) for (int i = (a); i >= (b); i--) #define REP(i,n) FOR(i,0,(int)(n)-1) #define st first #define nd second #define ALL(x) (x).begin(), (x).end() #define SZ(x) ((int)(x).size()) #define VI vector<int> #define PII pair<int,int> #define LD long double struct fast_hash { size_t operator()(int x) const { x = ((x >> 16) ^ x) * 0x45d9f3b; x = ((x >> 16) ^ x) * 0x45d9f3b; x = (x >> 16) ^ x; return x; } size_t operator()(const void* p) const { return operator()((int)(intptr_t)p); } }; template<class K, class V> struct HashMap : unordered_map<K, V, fast_hash> { HashMap() { this->max_load_factor(0.25); } }; struct HashSet : unordered_set<int, fast_hash> { HashSet() { this->max_load_factor(0.25); } }; template<class C> void mini(C& a4, C b4) { a4 = min(a4, b4); } template<class C> void maxi(C& a4, C b4) { a4 = max(a4, b4); } template<class L, class R> ostream &operator<<(ostream &os, pair<L,R> P) { return os << "(" << P.st << "," << P.nd << ")"; } template<class T> ostream &operator<<(ostream &os, vector<T> V){ os<<"[";for(auto vv:V)os<<vv<<",";return os<<"]"; } template<class TH> void _dbg(const char *sdbg, TH h){cerr<<sdbg<<"="<<h<<"\n";} template<class TH, class... TA> void _dbg(const char *sdbg, TH h, TA... a) { while(*sdbg!=',')cerr<<*sdbg++; cerr<<"="<<h<<","; _dbg(sdbg+1, a...); } #ifdef LOCAL #define debug(...) _dbg(#__VA_ARGS__, __VA_ARGS__) #else #define debug(...) (__VA_ARGS__) #define cerr if(0)cout #endif vector<VI> g; VI get_code(const VI& lab) { int n = SZ(g); VI deg(n); vector<bool> alive(n, true); REP(v, n) deg[v] = SZ(g[v]); priority_queue<PII, vector<PII>, greater<PII>> leaves; REP(v, n) if (deg[v] == 1) leaves.push({lab[v], v}); VI code; REP(step, n - 2) { int leaf = -1; while (SZ(leaves)) { auto [lbl, v] = leaves.top(); leaves.pop(); if (!alive[v] || deg[v] != 1 || lab[v] != lbl) continue; leaf = v; break; } int par = -1; for (int u : g[leaf]) if (alive[u]) { par = u; break; } code.PB(lab[par]); alive[leaf] = false; deg[leaf]--; deg[par]--; if (deg[par] == 1) leaves.push({lab[par], par}); } return code; } VI solve() { int n = SZ(g); VI perm(n); iota(ALL(perm), 1); VI best; bool has_best = false; do { VI code = get_code(perm); if (!has_best || code < best) { best = code; has_best = true; } } while (next_permutation(ALL(perm))); return best; } void print_ans(const VI& ans) { REP(i, SZ(ans)) { if (i) cout << ' '; cout << ans[i]; } cout << '\n'; } signed main() { ios_base::sync_with_stdio(0); cin.tie(0); int t; cin >> t; while (t--) { int n; cin >> n; g.assign(n, {}); REP(i, n - 1) { int a, b; cin >> a >> b; a--; b--; g[a].PB(b); g[b].PB(a); } print_ans(solve()); } return 0; } |
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