답안 #471501

# 제출 시각 아이디 문제 언어 결과 실행 시간 메모리
471501 2021-09-09T14:52:02 Z NhatMinh0208 Cat (info1cup19_cat) C++14
100 / 100
563 ms 30328 KB
#ifndef CPL_TEMPLATE
#define CPL_TEMPLATE
/*
	Normie's Template v2.5
	Changes:
    Added warning against using pragmas on USACO.
*/
// Standard library in one include.
#include <bits/stdc++.h>
using namespace std;
 
// ordered_set library.
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>
using namespace __gnu_pbds;
#define ordered_set(el) tree<el,null_type,less<el>,rb_tree_tag,tree_order_statistics_node_update>
 
// AtCoder library. (Comment out these two lines if you're not submitting in AtCoder.) (Or if you want to use it in other judges, run expander.py first.)
//#include <atcoder/all>
//using namespace atcoder;

//Pragmas (Comment out these three lines if you're submitting in szkopul or USACO.)
#pragma comment(linker, "/stack:200000000")
#pragma GCC optimize("Ofast,unroll-loops,tree-vectorize")
#pragma GCC target("sse,sse2,sse3,ssse3,sse4,popcnt,abm,mmx,avx,avx2,tune=native")
 
//File I/O.
#define FILE_IN "cseq.inp"
#define FILE_OUT "cseq.out"
#define ofile freopen(FILE_IN,"r",stdin);freopen(FILE_OUT,"w",stdout)
 
//Fast I/O.
#define fio ios::sync_with_stdio(0);cin.tie(0)
#define nfio cin.tie(0)
#define endl "\n"
 
//Order checking.
#define ord(a,b,c) ((a>=b)and(b>=c))
 
//min/max redefines, so i dont have to resolve annoying compile errors.
#define min(a,b) (((a)<(b))?(a):(b))
#define max(a,b) (((a)>(b))?(a):(b))

// Fast min/max assigns to use with AVX.
// Requires g++ 9.2.0.
template<typename T>
__attribute__((always_inline)) void chkmin(T& a, const T& b) {
    a=(a<b)?a:b;
}

template<typename T>
__attribute__((always_inline)) void chkmax(T& a, const T& b) {
    a=(a>b)?a:b;
}
 
//Constants.
#define MOD (ll(998244353))
#define MAX 300001
#define mag 320
const long double PI=3.14159265358979;
 
//Pairs and 3-pairs.
#define p1 first
#define p2 second.first
#define p3 second.second
#define fi first
#define se second
#define pii(element_type) pair<element_type,element_type>
#define piii(element_type) pair<element_type,pii(element_type)>
 
//Quick power of 2.
#define pow2(x) (ll(1)<<x)
 
//Short for-loops.
#define ff(i,__,___) for(int i=__;i<=___;i++)
#define rr(i,__,___) for(int i=__;i>=___;i--)
 
//Typedefs.
#define bi BigInt
typedef long long ll;
typedef long double ld;
typedef short sh;

// Binpow and stuff
ll BOW(ll a, ll x, ll p)
{
	if (!x) return 1;
	ll res=BOW(a,x/2,p);
	res*=res;
	res%=p;
	if (x%2) res*=a;
	return res%p;
}
ll INV(ll a, ll p)
{
	return BOW(a,p-2,p);
}
//---------END-------//
#endif
vector<int> vec;
vector<pii(int)> seq;
int n,m,i,j,k,t,t1,u,v,a,b;
int arr[200001];
int brr[100001];
int crr[100001];
int used[100001];
int main()
{
	fio;
    cin>>t;
    for (t1=0;t1<t;t1++) {
        cin>>n;
        seq.clear();
        for (i=1;i<=n;i++) {
            cin>>arr[i];
        }
        for (i=1;i<=n/2;i++) if (arr[i]+arr[n+1-i] != n+1) {
            cout<<-1<<endl;
            break;
        }
        if (i<=n/2) {
            continue;
        }
        for (i=1;i<=n/2;i++) {
            if (arr[i]<=n/2) {
                crr[arr[i]]=0;
                brr[arr[i]]=i;
            } else {
                crr[n+1-arr[i]]=1;
                brr[n+1-arr[i]]=i;
            }
            used[i]=0;
        }
        for (i=1;i<=n/2;i++) if (!used[i]) {
            u=i;
            vec.clear();
            while(true) {
                used[u]=1;
                vec.push_back(u);
                u=brr[u];
                if (used[u]) break;
            }

            for (j=1;j<vec.size();j++) {
                u=vec[0];
                v=vec[j];
                if (crr[v]) {
                    crr[u]^=1;
                    crr[v]^=1;
                    seq.push_back({brr[u],n+1-brr[v]});
                } else {
                    seq.push_back({brr[u],brr[v]});
                }
                swap(brr[u],brr[v]);
            }
        }
        vec.clear();
        for (i=1;i<=n/2;i++) if (crr[i]) {
            vec.push_back(i);
        }
        if (vec.size()%2) {
            cout<<-1<<endl;
            continue;
        } else {
            for (i=0;i<vec.size();i+=2) {
                u=vec[i];
                v=vec[i+1];
                seq.push_back({brr[u],brr[v]});
                seq.push_back({brr[u],n+1-brr[v]});
            }
        }
        cout<<seq.size()<<' '<<seq.size()<<endl;
        for (auto g : seq) {
            cout<<g.fi<<' '<<g.se<<endl;
        }
    }
}
// Normie28;
/*
abcd
badc
dcba
cdab

*/

Compilation message

cat.cpp:23: warning: ignoring '#pragma comment ' [-Wunknown-pragmas]
   23 | #pragma comment(linker, "/stack:200000000")
      | 
cat.cpp: In function 'int main()':
cat.cpp:144:23: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
  144 |             for (j=1;j<vec.size();j++) {
      |                      ~^~~~~~~~~~~
cat.cpp:165:23: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
  165 |             for (i=0;i<vec.size();i+=2) {
      |                      ~^~~~~~~~~~~
# 결과 실행 시간 메모리 Grader output
1 Correct 5 ms 332 KB Output is correct
# 결과 실행 시간 메모리 Grader output
1 Correct 24 ms 1016 KB Output is correct
2 Correct 24 ms 972 KB Output is correct
# 결과 실행 시간 메모리 Grader output
1 Correct 5 ms 332 KB Output is correct
2 Correct 24 ms 1016 KB Output is correct
3 Correct 24 ms 972 KB Output is correct
4 Correct 27 ms 1016 KB Output is correct
5 Correct 10 ms 596 KB Output is correct
6 Correct 8 ms 588 KB Output is correct
# 결과 실행 시간 메모리 Grader output
1 Correct 24 ms 1016 KB Output is correct
2 Correct 24 ms 972 KB Output is correct
3 Correct 538 ms 28316 KB Output is correct
4 Correct 500 ms 27500 KB Output is correct
5 Correct 549 ms 30328 KB Output is correct
# 결과 실행 시간 메모리 Grader output
1 Correct 5 ms 332 KB Output is correct
2 Correct 24 ms 1016 KB Output is correct
3 Correct 24 ms 972 KB Output is correct
4 Correct 27 ms 1016 KB Output is correct
5 Correct 10 ms 596 KB Output is correct
6 Correct 8 ms 588 KB Output is correct
7 Correct 538 ms 28316 KB Output is correct
8 Correct 500 ms 27500 KB Output is correct
9 Correct 549 ms 30328 KB Output is correct
10 Correct 535 ms 25208 KB Output is correct
11 Correct 485 ms 23552 KB Output is correct
12 Correct 538 ms 28724 KB Output is correct
13 Correct 563 ms 29632 KB Output is correct
14 Correct 515 ms 28400 KB Output is correct