#include <ios>
#include <iostream>
#include <utility>
#include <vector>
#include <map>
#include <algorithm>
#define nl '\n'
using namespace std;
int n;
vector<int> h,h2;
map<int,int> m;
vector<vector<pair<int,int>>> changes;
bool used[3007];
int main()
{
ios_base::sync_with_stdio(0);
cin.tie(0);
cin>>n;
for(int i=0; i<n; ++i){
int tmp;
cin>>tmp;
h.push_back(tmp);
h2.push_back(tmp);
}
sort(h2.begin(),h2.end());
for(int i=0; i<n; ++i){
m[h2[i]] = i;
}
/*for(int i=0; i<n; ++i){
h[i] = m[h[i]];
}*/
int j=0;
vector<pair<int,int>> a;
changes.push_back(a);
while(j<n){
for(int i=0; i<n; ++i){
int index_doc = m[h[i]];
if(i!=index_doc){
if(!used[h[i]]&&!used[h[index_doc]]){
changes.back().push_back({i,index_doc});
swap(h[i],h[index_doc]);
used[h[index_doc]] = true;
used[h[i]] = true;
}
}
}
if(changes.back().empty()){
break;
}
vector<pair<int,int>> a;
changes.push_back(a);
for(int i=0; i<3004; ++i){
used[i] = false;
}
++j;
}
cout<<changes.size()-1<<nl;
for(auto it:changes){
if(it.empty()){
break;
}
cout<<it.size()*2<<nl;
for(int i=0; i<it.size(); ++i){
cout<<it[i].first+1<<' ';
}
for(int i=it.size()-1; i>=0; --i){
cout<<it[i].second+1<<' ';
}
cout<<nl;
}
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 | #include <ios> #include <iostream> #include <utility> #include <vector> #include <map> #include <algorithm> #define nl '\n' using namespace std; int n; vector<int> h,h2; map<int,int> m; vector<vector<pair<int,int>>> changes; bool used[3007]; int main() { ios_base::sync_with_stdio(0); cin.tie(0); cin>>n; for(int i=0; i<n; ++i){ int tmp; cin>>tmp; h.push_back(tmp); h2.push_back(tmp); } sort(h2.begin(),h2.end()); for(int i=0; i<n; ++i){ m[h2[i]] = i; } /*for(int i=0; i<n; ++i){ h[i] = m[h[i]]; }*/ int j=0; vector<pair<int,int>> a; changes.push_back(a); while(j<n){ for(int i=0; i<n; ++i){ int index_doc = m[h[i]]; if(i!=index_doc){ if(!used[h[i]]&&!used[h[index_doc]]){ changes.back().push_back({i,index_doc}); swap(h[i],h[index_doc]); used[h[index_doc]] = true; used[h[i]] = true; } } } if(changes.back().empty()){ break; } vector<pair<int,int>> a; changes.push_back(a); for(int i=0; i<3004; ++i){ used[i] = false; } ++j; } cout<<changes.size()-1<<nl; for(auto it:changes){ if(it.empty()){ break; } cout<<it.size()*2<<nl; for(int i=0; i<it.size(); ++i){ cout<<it[i].first+1<<' '; } for(int i=it.size()-1; i>=0; --i){ cout<<it[i].second+1<<' '; } cout<<nl; } return 0; } |
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