/*
Jakub Żojdzik
15-12-2022
*/
#include <bits/stdc++.h>
#ifdef LOCAL
#include "debug.hpp"
#else
#define debug(...)
#define dt
#endif
using namespace std;
typedef long long ll;
typedef unsigned long long ull;
typedef double db;
typedef pair<int, int> pii;
typedef pair<long long, long long> pll;
typedef vector<int> vi;
typedef vector<long long> vll;
typedef vector<pair<int, int>> vpii;
typedef vector<pair<long long, long long>> vpll;
#define fi first
#define se second
#define pb push_back
#define rep(i, x, y) for(ll i = (ll)x; i <= (ll)y; i++)
#define all(x) x.begin(), x.end()
#define sz(x) (ll)(x).size()
#define nl cout << '\n'
vpii input;
int h[3007];
bitset<3007> seen;
deque<int> res[3007];
int itr;
int main()
{
cout.tie(0);
cin.tie(0)->sync_with_stdio(0);
int n, tmp;
cin >> n;
for(int i = 0; i < n; i++)
{
cin >> tmp;
input.pb({tmp, i});
}
sort(all(input));
int rozne = 0;
rep(i, 0, n-1)
{
h[input[i].se] = i;
rozne += (i != h[i]);
}
while(rozne)
{
seen.reset();
for(int i = 0; i < n; i++)
{
vi cykl;
if(seen[i] || i == h[i]) continue;
int akt = i;
while(!seen[akt])
{
cykl.pb(akt);
seen[akt] = 1;
akt = h[akt];
}
if(sz(cykl) == 2)
{
res[itr].push_back(cykl[0]);
res[itr].push_front(cykl[1]);
swap(h[cykl[0]], h[cykl[1]]);
}
else
{
for(int j = 1; j <= (sz(cykl)-1)/2; j++)
{
res[itr].push_back(cykl[j]);
res[itr].push_front(cykl[sz(cykl)-j]);
swap(h[cykl[j]], h[cykl[sz(cykl)-j]]);
}
}
rozne = 0;
for(int i = 0; i < n; i++)
{
rozne += (h[i] != i);
}
}
itr++;
}
cout << itr << '\n';
for(int i = 0; i < itr; i++)
{
cout << sz(res[i]) << '\n';
for(int x : res[i])
{
cout << x+1 << ' ';
}
nl;
}
}
/*
*/
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 | /* Jakub Żojdzik 15-12-2022 */ #include <bits/stdc++.h> #ifdef LOCAL #include "debug.hpp" #else #define debug(...) #define dt #endif using namespace std; typedef long long ll; typedef unsigned long long ull; typedef double db; typedef pair<int, int> pii; typedef pair<long long, long long> pll; typedef vector<int> vi; typedef vector<long long> vll; typedef vector<pair<int, int>> vpii; typedef vector<pair<long long, long long>> vpll; #define fi first #define se second #define pb push_back #define rep(i, x, y) for(ll i = (ll)x; i <= (ll)y; i++) #define all(x) x.begin(), x.end() #define sz(x) (ll)(x).size() #define nl cout << '\n' vpii input; int h[3007]; bitset<3007> seen; deque<int> res[3007]; int itr; int main() { cout.tie(0); cin.tie(0)->sync_with_stdio(0); int n, tmp; cin >> n; for(int i = 0; i < n; i++) { cin >> tmp; input.pb({tmp, i}); } sort(all(input)); int rozne = 0; rep(i, 0, n-1) { h[input[i].se] = i; rozne += (i != h[i]); } while(rozne) { seen.reset(); for(int i = 0; i < n; i++) { vi cykl; if(seen[i] || i == h[i]) continue; int akt = i; while(!seen[akt]) { cykl.pb(akt); seen[akt] = 1; akt = h[akt]; } if(sz(cykl) == 2) { res[itr].push_back(cykl[0]); res[itr].push_front(cykl[1]); swap(h[cykl[0]], h[cykl[1]]); } else { for(int j = 1; j <= (sz(cykl)-1)/2; j++) { res[itr].push_back(cykl[j]); res[itr].push_front(cykl[sz(cykl)-j]); swap(h[cykl[j]], h[cykl[sz(cykl)-j]]); } } rozne = 0; for(int i = 0; i < n; i++) { rozne += (h[i] != i); } } itr++; } cout << itr << '\n'; for(int i = 0; i < itr; i++) { cout << sz(res[i]) << '\n'; for(int x : res[i]) { cout << x+1 << ' '; } nl; } } /* */ |
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