CHFCH Tester

//teja349
#include <bits/stdc++.h>
#include <vector>
#include <set>
#include <map>
#include <string>
#include <cstdio>
#include <cstdlib>
#include <climits>
#include <utility>
#include <algorithm>
#include <cmath>
#include <queue>
#include <stack>
#include <iomanip>
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>
//setbase - cout << setbase (16); cout << 100 << endl; Prints 64
//setfill -   cout << setfill ('x') << setw (5); cout << 77 << endl; prints xxx77
//setprecision - cout << setprecision (14) << f << endl; Prints x.xxxx
//cout.precision(x)  cout<<fixed<<val;  // prints x digits after decimal in val

using namespace std;
using namespace __gnu_pbds;

#define f(i,a,b) for(i=a;i<b;i++)
#define rep(i,n) f(i,0,n)
#define fd(i,a,b) for(i=a;i>=b;i--)
#define pb push_back
#define mp make_pair
#define vi vector< int >
#define vl vector< ll >
#define ss second
#define ff first
#define ll long long
#define pii pair< int,int >
#define pll pair< ll,ll >
#define sz(a) a.size()
#define inf (1000*1000*1000+5)
#define all(a) a.begin(),a.end()
#define tri pair<int,pii>
#define vii vector<pii>
#define vll vector<pll>
#define viii vector<tri>
#define mod (1000*1000*1000+7)
#define pqueue priority_queue< int >
#define pdqueue priority_queue< int,vi ,greater< int > >
#define flush fflush(stdout)
#define primeDEN 727999983
mt19937 rng(chrono::steady_clock::now().time_since_epoch().count());

// find_by_order()  // order_of_key
typedef tree<
int,
null_type,
less<int>,
rb_tree_tag,
tree_order_statistics_node_update>
ordered_set;
#define int ll
vector<vi> vec(312345);
int pre[312345];
int getapsum(int val){
    return val*(val+1)/2;
}
int getsum(int i,int j){
    if(i==0)
        return pre[j];
    return pre[j]-pre[i-1];
}
int a[312345],done[312345];
main(){
    std::ios::sync_with_stdio(false); cin.tie(NULL);
    int t;
    cin>>t;
    while(t--){
        int n,k;
        cin>>n>>k;
        int i;
        map<int,int> mapi;
        rep(i,n){
            cin>>a[i];
            done[a[i]]=0;
            vec[a[i]].pb(i);
        }
        int val,lef,rig,j,ans,mini,iinf;
        iinf=inf;
        iinf*=inf;
        mini=iinf;
        rep(i,n){
            if(done[a[i]])
                continue;
            done[a[i]]=1;
            if(vec[a[i]].size()<k){
                vec[a[i]].clear();
                continue;
            }
            val=a[i];
            lef=k/2;
            rig=k-lef;
            rep(j,vec[val].size()){
                if(j==0){
                    pre[j]=vec[val][j];
                }
                else{
                    pre[j]=pre[j-1]+vec[val][j];
                }
            }
            f(j,k/2,vec[val].size()){
                if(j+rig-1==vec[val].size())
                    break;
                ans=getapsum(vec[val][j]-1)-getapsum(vec[val][j]-lef-1)-getsum(j-lef,j-1);
                ans+=getsum(j,j+rig-1)-getapsum(vec[val][j]+rig-1)+getapsum(vec[val][j]-1);
                mini=min(mini,ans);
            }
            vec[val].clear();

        }
        if(mini==iinf)
            mini=-1;
        cout<<mini<<endl;

    }
    return 0;
}