//
#ifndef __SIZEOF_INT128__
#define __SIZEOF_INT128__
#endif
#pragma GCC optimize("Ofast")
#include <bits/stdc++.h>
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>
#include <ext/pb_ds/priority_queue.hpp>
using namespace std;
using namespace chrono;
using namespace __gnu_pbds;
template <typename T> using oset = tree<T, null_type, less_equal<T>, rb_tree_tag, tree_order_statistics_node_update>;
#define rep(i, p, k) for(int i(p); i < k; ++i)
#define per(i, p, k) for(int i(p); i > k; --i)
#define sz(x) (int)x.size()
#define sc static_cast
typedef long long ll;
typedef long double ld;
typedef unsigned int uint;
typedef unsigned long long ull;
typedef __int128_t lll;
//#define int ll
template <typename T = int> using par = std::pair <T, T>;
#define fir first
#define sec second
#define test int _number_of_tests(in()); while(_number_of_tests--)
#define all(x) (x).begin(), (x).end()
#define rall(x) (x).rbegin(), (x).rend()
#define pb emplace_back
struct Timer {
string name{""};
time_point<high_resolution_clock> end, start{high_resolution_clock::now()};
duration<float, std::milli> dur;
Timer() = default;
Timer(string name): name(name) {}
~Timer() {
end = high_resolution_clock::now(); dur= end - start;
cout << "@" << name << "> " << dur.count() << " ms" << '\n';
}
};
template <typename T = int> inline T in()
{
T x;
std::cin >> x;
return x;
}
std::string yn(bool b)
{
if(b) return "YES\n";
else return "NO\n";
}
template <typename F, typename S> std::ostream& operator<<(std::ostream& out, const std::pair <F, S>& par);
template <typename T> std::ostream& operator<< (std::ostream& out, const std::vector <T>& wek)
{
for(const auto& i : wek)out << i << ' ';
return out;
}
template <typename F, typename S> std::ostream& operator<<(std::ostream& out, const std::pair <F, S>& par)
{
out << '{'<<par.first<<", "<<par.second<<"}";
return out;
}
#define show(x) cout << #x << " = " << x << '\n';
constexpr int MAXN = 3003;
const vector <int> EMPTY = {};
pair <int, int> tab[MAXN];
int gra[MAXN];
bool byl[MAXN];
array<par <vector <int>>, 2> odp;
std::int32_t main()
{
std::cin.tie(nullptr); std::cout.tie(nullptr); std::ios_base::sync_with_stdio(0);
int n(in());
rep(i, 1, n+1){
cin >> tab[i].first;
tab[i].second = i;
}
sort(&tab[1], &tab[n+1]);
rep(i, 1, n+1)gra[tab[i].second] = i;
rep(i, 1, n+1)if(!byl[i]){
byl[i] = 1;
vector <int> c{i};
for(int j(gra[i]); j != i; j = gra[j]){
c.pb(j);
byl[j] = 1;
}
if(sz(c) == 1)continue;
if(sz(c) == 2){
odp[0].first.pb(c[0]);
odp[0].second.pb(c[1]);
continue;
}
for(auto x: {0, 1})for(int p(x), k(sz(c)-1); k > p; ++p, --k){
odp[x].first.pb(c[p]);
odp[x].second.pb(c[k]);
}
}
if(sz(odp[1].first))cout << "2\n";
else if(sz(odp[0].first))cout << "1\n";
else cout << "0\n";
for(auto& o: odp)if(sz(o.first)){
cout << sz(o.first)*2 << '\n';
for(auto i: o.first)cout << i << ' ';
reverse(all(o.second));
for(auto i: o.second)cout << i << ' ';
cout << '\n';
}
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 | // #ifndef __SIZEOF_INT128__ #define __SIZEOF_INT128__ #endif #pragma GCC optimize("Ofast") #include <bits/stdc++.h> #include <ext/pb_ds/assoc_container.hpp> #include <ext/pb_ds/tree_policy.hpp> #include <ext/pb_ds/priority_queue.hpp> using namespace std; using namespace chrono; using namespace __gnu_pbds; template <typename T> using oset = tree<T, null_type, less_equal<T>, rb_tree_tag, tree_order_statistics_node_update>; #define rep(i, p, k) for(int i(p); i < k; ++i) #define per(i, p, k) for(int i(p); i > k; --i) #define sz(x) (int)x.size() #define sc static_cast typedef long long ll; typedef long double ld; typedef unsigned int uint; typedef unsigned long long ull; typedef __int128_t lll; //#define int ll template <typename T = int> using par = std::pair <T, T>; #define fir first #define sec second #define test int _number_of_tests(in()); while(_number_of_tests--) #define all(x) (x).begin(), (x).end() #define rall(x) (x).rbegin(), (x).rend() #define pb emplace_back struct Timer { string name{""}; time_point<high_resolution_clock> end, start{high_resolution_clock::now()}; duration<float, std::milli> dur; Timer() = default; Timer(string name): name(name) {} ~Timer() { end = high_resolution_clock::now(); dur= end - start; cout << "@" << name << "> " << dur.count() << " ms" << '\n'; } }; template <typename T = int> inline T in() { T x; std::cin >> x; return x; } std::string yn(bool b) { if(b) return "YES\n"; else return "NO\n"; } template <typename F, typename S> std::ostream& operator<<(std::ostream& out, const std::pair <F, S>& par); template <typename T> std::ostream& operator<< (std::ostream& out, const std::vector <T>& wek) { for(const auto& i : wek)out << i << ' '; return out; } template <typename F, typename S> std::ostream& operator<<(std::ostream& out, const std::pair <F, S>& par) { out << '{'<<par.first<<", "<<par.second<<"}"; return out; } #define show(x) cout << #x << " = " << x << '\n'; constexpr int MAXN = 3003; const vector <int> EMPTY = {}; pair <int, int> tab[MAXN]; int gra[MAXN]; bool byl[MAXN]; array<par <vector <int>>, 2> odp; std::int32_t main() { std::cin.tie(nullptr); std::cout.tie(nullptr); std::ios_base::sync_with_stdio(0); int n(in()); rep(i, 1, n+1){ cin >> tab[i].first; tab[i].second = i; } sort(&tab[1], &tab[n+1]); rep(i, 1, n+1)gra[tab[i].second] = i; rep(i, 1, n+1)if(!byl[i]){ byl[i] = 1; vector <int> c{i}; for(int j(gra[i]); j != i; j = gra[j]){ c.pb(j); byl[j] = 1; } if(sz(c) == 1)continue; if(sz(c) == 2){ odp[0].first.pb(c[0]); odp[0].second.pb(c[1]); continue; } for(auto x: {0, 1})for(int p(x), k(sz(c)-1); k > p; ++p, --k){ odp[x].first.pb(c[p]); odp[x].second.pb(c[k]); } } if(sz(odp[1].first))cout << "2\n"; else if(sz(odp[0].first))cout << "1\n"; else cout << "0\n"; for(auto& o: odp)if(sz(o.first)){ cout << sz(o.first)*2 << '\n'; for(auto i: o.first)cout << i << ' '; reverse(all(o.second)); for(auto i: o.second)cout << i << ' '; cout << '\n'; } return 0; } |
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