#include <vector> #include <iostream> #include <sstream> #include <math.h> #include <sys/time.h> #include <cstdlib> #include <algorithm> #include <cassert> #include <cstring> #include <fstream> #include <set> #include <map> #include <iomanip> #include <queue> #define FOR(i,a,b) for(__typeof(b) i=(a);i<(b);++i) #define REP(i,a) FOR(i,0,a) #define FOREACH(x,c) for(__typeof(c.begin()) x=c.begin();x != c.end(); x++) #define ALL(c) c.begin(),c.end() #define CLEAR(c) memset(c,0,sizeof(c)) #define SIZE(c) (int) ((c).size()) #define PB push_back #define MP make_pair #define X first #define Y second #define ULL unsigned long long #define LL long long #define LD long double #define II pair<int, int> #define DD pair<double, double> #define FF pair<float,float> #define VC vector #define VI VC<int> #define VVI VC<VI> #define VVVI VC<VVI> #define VD VC<double> #define VS VC<string> #define VII VC<II> #define VDD VC<DD> #define VFF VC<FF> #define VVD VC<VD> #define VVVD VC<VVD> #define VULL VC<ULL> #define DB(a) cerr << #a << ": " << a << endl; using namespace std; template<class T> void print(VC < T > v) {cerr << "[";if (SIZE(v) != 0) cerr << v[0]; FOR(i, 1, SIZE(v)) cerr << "," << v[i]; cerr << "]\n";} template<class T> string i2s(T &x) { ostringstream o; o << x; return o.str(); } VS split(string &s, char c = ' ') {VS all; int p = 0, np; while (np = s.find(c, p), np >= 0) {all.PB(s.substr(p, np - p)); p = np + 1;} if (p < SIZE(s)) all.PB(s.substr(p)); return all;} int main(int argc, char *argv[]){ int N; VI p; cin >> N; p.resize(N); REP(i,N) cin >> p[i]; VII order(N); REP(i,N) order[i] = MP(p[i],i); sort(ALL(order)); REP(i,N) p[order[i].Y] = i; // generate cycle lists and then? VVI cycles; VI used(N,0); REP(i,N) if (!used[i]){ int j = i; cycles.PB(VI()); do{ used[j] = 1; cycles.back().PB(j); j = p[j]; } while(!used[j]); } int M = 0; for(auto c : cycles) M = max(M,SIZE(c)); int R; if (M == 1) R = 0; else if (M == 2) R = 1; else R = 2; cout << R << endl; REP(r,R){ VI p1; VI p2; for(auto c : cycles){ int a = r; int b = SIZE(c)-1; while(a < b){ p1.PB(c[a]); p2.PB(c[b]); a++; b--; }; } cout << 2*SIZE(p1) << endl; REP(i,SIZE(p1)) cout << p1[i]+1 << " "; for(int i=SIZE(p2)-1; i >= 0; i--) cout << p2[i]+1 << " "; cout << endl; } 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 | #include <vector> #include <iostream> #include <sstream> #include <math.h> #include <sys/time.h> #include <cstdlib> #include <algorithm> #include <cassert> #include <cstring> #include <fstream> #include <set> #include <map> #include <iomanip> #include <queue> #define FOR(i,a,b) for(__typeof(b) i=(a);i<(b);++i) #define REP(i,a) FOR(i,0,a) #define FOREACH(x,c) for(__typeof(c.begin()) x=c.begin();x != c.end(); x++) #define ALL(c) c.begin(),c.end() #define CLEAR(c) memset(c,0,sizeof(c)) #define SIZE(c) (int) ((c).size()) #define PB push_back #define MP make_pair #define X first #define Y second #define ULL unsigned long long #define LL long long #define LD long double #define II pair<int, int> #define DD pair<double, double> #define FF pair<float,float> #define VC vector #define VI VC<int> #define VVI VC<VI> #define VVVI VC<VVI> #define VD VC<double> #define VS VC<string> #define VII VC<II> #define VDD VC<DD> #define VFF VC<FF> #define VVD VC<VD> #define VVVD VC<VVD> #define VULL VC<ULL> #define DB(a) cerr << #a << ": " << a << endl; using namespace std; template<class T> void print(VC < T > v) {cerr << "[";if (SIZE(v) != 0) cerr << v[0]; FOR(i, 1, SIZE(v)) cerr << "," << v[i]; cerr << "]\n";} template<class T> string i2s(T &x) { ostringstream o; o << x; return o.str(); } VS split(string &s, char c = ' ') {VS all; int p = 0, np; while (np = s.find(c, p), np >= 0) {all.PB(s.substr(p, np - p)); p = np + 1;} if (p < SIZE(s)) all.PB(s.substr(p)); return all;} int main(int argc, char *argv[]){ int N; VI p; cin >> N; p.resize(N); REP(i,N) cin >> p[i]; VII order(N); REP(i,N) order[i] = MP(p[i],i); sort(ALL(order)); REP(i,N) p[order[i].Y] = i; // generate cycle lists and then? VVI cycles; VI used(N,0); REP(i,N) if (!used[i]){ int j = i; cycles.PB(VI()); do{ used[j] = 1; cycles.back().PB(j); j = p[j]; } while(!used[j]); } int M = 0; for(auto c : cycles) M = max(M,SIZE(c)); int R; if (M == 1) R = 0; else if (M == 2) R = 1; else R = 2; cout << R << endl; REP(r,R){ VI p1; VI p2; for(auto c : cycles){ int a = r; int b = SIZE(c)-1; while(a < b){ p1.PB(c[a]); p2.PB(c[b]); a++; b--; }; } cout << 2*SIZE(p1) << endl; REP(i,SIZE(p1)) cout << p1[i]+1 << " "; for(int i=SIZE(p2)-1; i >= 0; i--) cout << p2[i]+1 << " "; cout << endl; } return 0; } |