#include <bits/stdc++.h>
#define maxn 3005
using namespace std;
pair <int, int> wej[maxn];
int a[maxn];
int b[maxn];
int gdzie[maxn];
void napraw(int pos)
{
int wart = b[pos];
if(b[wart])
{
if(b[wart] != pos)
{
cout << "dupa\n";
exit(1);
}
}
else
{
b[wart] = pos;
napraw(wart);
}
if(!b[gdzie[wart]])
{
b[gdzie[wart]] = a[pos];
napraw(gdzie[wart]);
}
}
int main()
{
ios_base::sync_with_stdio(0);
cin.tie(0);
int n;
cin >> n;
for(int i = 1; i <= n; ++i)
{
cin >> wej[i].first;
wej[i].second = i;
}
sort(wej+1, wej+1+n);
for(int i = 1; i <= n; ++i) a[wej[i].second] = i;
//for(int i = 1; i <= n; ++i) cout << a[i] << " ";
//cout << "\n";
bool czy0 = 1;
for(int i = 1; i <= n; ++i) if(a[i] != i) czy0 = 0;
if(czy0)
{
cout << 0;
return 0;
}
for(int i = 1; i <= n; ++i) gdzie[a[i]] = i;
bool czy1 = 1;
for(int i = 1; i <= n; ++i) if(gdzie[i] != a[i]) czy1 = 0;
if(czy1)
{
cout << 1 << "\n";
vector <int> t;
for(int i = 1; i <= n; ++i) if(a[i] < i) t.emplace_back(i);
for(int i = n; i >= 1; --i) if(a[i] < i) t.emplace_back(a[i]);
cout << t.size() << "\n";
for(int i : t) cout << i << " ";
cout << "\n";
return 0;
}
for(int i = 1; i <= n; ++i)
{
if(!b[i])
{
b[i] = a[i];
napraw(i);
}
}
/*cout << "b: ";
for(int i = 1; i <= n; ++i) cout << b[i] << " ";
cout << "\n";*/
cout << 2 << "\n";
vector <int> t1, t2;
for(int i = 1; i <= n; ++i) if(i < gdzie[b[i]])
{
t1.emplace_back(i);
t2.emplace_back(gdzie[b[i]]);
}
for(int i = t2.size()-1; ~i; --i) t1.emplace_back(t2[i]);
cout << t1.size() << "\n";
for(int i : t1) cout << i << " ";
cout << "\n";
vector <int> t;
for(int i = 1; i <= n; ++i) if(b[i] < i) t.emplace_back(i);
for(int i = n; i >= 1; --i) if(b[i] < i) t.emplace_back(b[i]);
cout << t.size() << "\n";
for(int i : t) 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 99 100 101 102 103 104 105 106 107 108 109 110 111 | #include <bits/stdc++.h> #define maxn 3005 using namespace std; pair <int, int> wej[maxn]; int a[maxn]; int b[maxn]; int gdzie[maxn]; void napraw(int pos) { int wart = b[pos]; if(b[wart]) { if(b[wart] != pos) { cout << "dupa\n"; exit(1); } } else { b[wart] = pos; napraw(wart); } if(!b[gdzie[wart]]) { b[gdzie[wart]] = a[pos]; napraw(gdzie[wart]); } } int main() { ios_base::sync_with_stdio(0); cin.tie(0); int n; cin >> n; for(int i = 1; i <= n; ++i) { cin >> wej[i].first; wej[i].second = i; } sort(wej+1, wej+1+n); for(int i = 1; i <= n; ++i) a[wej[i].second] = i; //for(int i = 1; i <= n; ++i) cout << a[i] << " "; //cout << "\n"; bool czy0 = 1; for(int i = 1; i <= n; ++i) if(a[i] != i) czy0 = 0; if(czy0) { cout << 0; return 0; } for(int i = 1; i <= n; ++i) gdzie[a[i]] = i; bool czy1 = 1; for(int i = 1; i <= n; ++i) if(gdzie[i] != a[i]) czy1 = 0; if(czy1) { cout << 1 << "\n"; vector <int> t; for(int i = 1; i <= n; ++i) if(a[i] < i) t.emplace_back(i); for(int i = n; i >= 1; --i) if(a[i] < i) t.emplace_back(a[i]); cout << t.size() << "\n"; for(int i : t) cout << i << " "; cout << "\n"; return 0; } for(int i = 1; i <= n; ++i) { if(!b[i]) { b[i] = a[i]; napraw(i); } } /*cout << "b: "; for(int i = 1; i <= n; ++i) cout << b[i] << " "; cout << "\n";*/ cout << 2 << "\n"; vector <int> t1, t2; for(int i = 1; i <= n; ++i) if(i < gdzie[b[i]]) { t1.emplace_back(i); t2.emplace_back(gdzie[b[i]]); } for(int i = t2.size()-1; ~i; --i) t1.emplace_back(t2[i]); cout << t1.size() << "\n"; for(int i : t1) cout << i << " "; cout << "\n"; vector <int> t; for(int i = 1; i <= n; ++i) if(b[i] < i) t.emplace_back(i); for(int i = n; i >= 1; --i) if(b[i] < i) t.emplace_back(b[i]); cout << t.size() << "\n"; for(int i : t) cout << i << " "; cout << "\n"; return 0; } |
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