#include <map>

#include <set>

#include <list>

#include <cmath>

#include <queue>

#include <stack>

#include <cstdio>

#include <vector>

#include <string>

#include <cctype>

#include <complex>

#include <cassert>

#include <utility>

#include <cstring>

#include <cstdlib>

#include <iostream>

#include <algorithm>

using namespace std;

typedef pair<int,int> PII;

typedef long long ll;

#define lson l,m,rt<<1

#define pi acos(-1.0)

#define rson m+1,r,rt<<11

#define All 1,N,1

#define read freopen("in.txt", "r", stdin)

const ll  INFll = 0x3f3f3f3f3f3f3f3fLL;

const int INF= 0x7ffffff;

const int mod =  ;

int dp[][];

int l[];

int n,k;

void solve(){

   for(int i=;i<=n;++i){

    dp[i][]=;

    for(int j=;j<=k;++j)

        dp[i][j]=INF;

   }

    for(int i=;i<=n;++i)

        for(int j=;j<=k;++j)

            if(i>=*j&&dp[i-][j-]!=INF){

        dp[i][j]=min(dp[i-][j],dp[i-][j-]+(l[i]-l[i-])*(l[i]-l[i-]));

            }

    printf("%d\n",dp[n][k]);

}

int main()

{

    int t;

    scanf("%d",&t);

    while(t--){

        scanf("%d%d",&k,&n);

        for(int i=n;i>;--i)

            scanf("%d",&l[i]);

               k+=;

        solve();

    }

return ;

}