Educational Codeforces Round 129 (Rated for Div. 2) 1681C. Double Sort Solution

 

Problem Link:  https://codeforces.com/contest/1681/problem/c

Solve in C++:  

///La ilaha illellahu muhammadur rasulullah

///******Bismillahir-Rahmanir-Rahim******///

///Abul Hasnat  Tonmoy

///Department of CSE,23rd batch

///Islamic University,Bangladesh

///**********ALLAH IS ALMIGHTY************///

#include <bits/stdc++.h>

using namespace std;

int main()

{

    long long  x,t,i,j,e,n;

    cin>>t;

    while(t--)

    {

        e=0;

        vector<pair<int,int>>r;

        cin>>n;

        long long a[n+9],b[n+9];

        for(i=1; i<=n; i++)cin>>a[i];

        for(i=1; i<=n; i++)cin>>b[i];

        if(is_sorted(a+1,a+n+1)&&(is_sorted(b+1,b+n+1)))

            cout<<"0"<<endl;

        else

        {

            for(i=1; i<=n; i++)

            {

                for( j=1; j<n; j++)

                {

                    if(a[j]>a[j+1] || b[j]>b[j+1])

                    {

                        swap(a[j],a[j+1]);

                        swap(b[j],b[j+1]);

                        r.push_back({j,j+1});

                    }

                }

            }

            e=0;

            for(i=1; i<n; i++)

            {

                if((a[i]>a[i+1])||(b[i]>b[i+1]))

                {

                    e=1;

                    break;

                }

            }

            if(e==1)

                cout<<"-1"<<endl;

            else

            {

                cout<<r.size()<<endl;

                for(i=0; i<r.size(); i++)

                cout<<r[i].first<<" "<<r[i].second<<endl;

            }

        }

    }

}