#include <bits/stdc++.h>
using namespace std;
#define fwd(i, a, n) for (int i = (a); i < (n); i++)
#define rep(i, n) fwd(i, 0, n)
#define all(X) X.begin(), X.end()
#define sz(X) int(size(X))
#define pb push_back
#define eb emplace_back
#define st first
#define nd second
using pii = pair<int, int>;
using vi = vector<int>;
using ll = long long;
using ld = long double;
#ifdef LOC
auto SS = signal(6, [](int) {
*(int *)0 = 0;
});
# define DTP(x, y) \
auto operator<<(auto &o, auto a)->decltype(y, o) { \
o << "("; \
x; \
return o << ")"; \
}
DTP(o << a.st << ", " << a.nd, a.nd);
DTP(for (auto i : a) o << i << ", ", all(a));
void dump(auto... x) {
((cerr << x << ", "), ...) << '\n';
}
# define deb(x...) cerr << setw(4) << __LINE__ << ":[" #x "]: ", dump(x)
#else
# define deb(...) 0
#endif
vi prufer_code(const vi &labeling, const vector<vi> &g) {
int n = sz(labeling);
vector<vi> g2(n);
rep(i, n) {
for (int j : g[i]) {
g2[labeling[i]].pb(labeling[j]);
}
}
vi deg(n);
rep(i, n) {
deg[i] = sz(g2[i]);
}
vi code;
rep(i, n - 2) {
int leaf = -1;
rep(j, n) {
if (deg[j] == 1) {
leaf = j;
break;
}
}
int par = -1;
for (int j : g2[leaf]) {
if (deg[j] > 0) {
par = j;
break;
}
}
code.pb(par);
deg[leaf]--;
deg[par]--;
}
return code;
}
void sol() {
int n;
cin >> n;
vector<vi> g(n);
rep(i, n - 1) {
int a, b;
cin >> a >> b;
a--, b--;
g[a].pb(b);
g[b].pb(a);
}
vi opt_code(n - 2, n);
vi labeling(n);
iota(all(labeling), 0);
do {
opt_code = min(opt_code, prufer_code(labeling, g));
} while (next_permutation(all(labeling)));
for (int x : opt_code) {
cout << x + 1 << " ";
}
cout << "\n";
}
int32_t main() {
cin.tie(0)->sync_with_stdio(0);
int t;
cin >> t;
rep(i, t) {
sol();
}
#ifdef LOCF
cout.flush();
cerr << "- - - - - - - - -\n";
(void)!system(
"grep VmPeak /proc/$PPID/status | sed s/....kB/\' MB\'/1 >&2"); // 4x.kB
// ....kB
#endif
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 | #include <bits/stdc++.h> using namespace std; #define fwd(i, a, n) for (int i = (a); i < (n); i++) #define rep(i, n) fwd(i, 0, n) #define all(X) X.begin(), X.end() #define sz(X) int(size(X)) #define pb push_back #define eb emplace_back #define st first #define nd second using pii = pair<int, int>; using vi = vector<int>; using ll = long long; using ld = long double; #ifdef LOC auto SS = signal(6, [](int) { *(int *)0 = 0; }); # define DTP(x, y) \ auto operator<<(auto &o, auto a)->decltype(y, o) { \ o << "("; \ x; \ return o << ")"; \ } DTP(o << a.st << ", " << a.nd, a.nd); DTP(for (auto i : a) o << i << ", ", all(a)); void dump(auto... x) { ((cerr << x << ", "), ...) << '\n'; } # define deb(x...) cerr << setw(4) << __LINE__ << ":[" #x "]: ", dump(x) #else # define deb(...) 0 #endif vi prufer_code(const vi &labeling, const vector<vi> &g) { int n = sz(labeling); vector<vi> g2(n); rep(i, n) { for (int j : g[i]) { g2[labeling[i]].pb(labeling[j]); } } vi deg(n); rep(i, n) { deg[i] = sz(g2[i]); } vi code; rep(i, n - 2) { int leaf = -1; rep(j, n) { if (deg[j] == 1) { leaf = j; break; } } int par = -1; for (int j : g2[leaf]) { if (deg[j] > 0) { par = j; break; } } code.pb(par); deg[leaf]--; deg[par]--; } return code; } void sol() { int n; cin >> n; vector<vi> g(n); rep(i, n - 1) { int a, b; cin >> a >> b; a--, b--; g[a].pb(b); g[b].pb(a); } vi opt_code(n - 2, n); vi labeling(n); iota(all(labeling), 0); do { opt_code = min(opt_code, prufer_code(labeling, g)); } while (next_permutation(all(labeling))); for (int x : opt_code) { cout << x + 1 << " "; } cout << "\n"; } int32_t main() { cin.tie(0)->sync_with_stdio(0); int t; cin >> t; rep(i, t) { sol(); } #ifdef LOCF cout.flush(); cerr << "- - - - - - - - -\n"; (void)!system( "grep VmPeak /proc/$PPID/status | sed s/....kB/\' MB\'/1 >&2"); // 4x.kB // ....kB #endif return 0; } |
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