Language: C++

#pragma GCC optimize ("O3")
#include <iostream>
#include <iomanip>
#include <istream>
#include <ostream>
#include <sstream>
#include <iterator>
#include <vector>
#include <algorithm>
#include <queue>
#include <deque>
#include <list>
#include <stack>
#include <map>
#include <unordered_map>
#include <set>
#include <bitset>
#include <utility>
#include <cmath>
#include <cstdio>
#include <cstring>
#include <string>
#include <ctime>
#include <cctype>
#include <cstdlib>
#define IINF 100000000
#define INF 300000000000000000
#define MOD 1000000007
#define mod 1000000007
#define REP(i, a, n) for (ll i = a; i < (ll)(n); i++)
#define REPE(i, a, n) for (ll i = a; i <= (ll)(n); i++)
#define Endl endl
#define fi first
#define se second
#define pb push_back
#define mp make_pair
#define mt make_tuple
#define eb emplace_back
#define mmax(x,y)(x>y?x:y)
#define mmin(x,y)(x<y?x:y)
#define chmax(x,y) x=mmax(x,y)
#define chmin(x,y) x=mmin(x,y)
#define all(x) (x).begin(),(x).end()
#define siz(x) (ll)(x).size()
#define PI acos(-1.0)
using namespace std;
typedef long long int ll;
typedef unsigned long long int ull;
typedef long double ld;
typedef pair<int,int>Pin;
typedef pair<ll,ll>Pll;
template<class T> using V=vector<T>;
long long GCD(long long a, long long b) {return b?GCD(b,a%b):a;}
long long LCM(long long a, long long b) {return a/GCD(a,b)*b;}
int dx[4]={-1,0,1,0};
int dy[4]={0,-1,0,1};
int ddx[8]={-1,0,1,0,1,1,-1,-1};
int ddy[8]={0,-1,0,1,1,-1,1,-1};
ll cmp(pair<ll,ll>a,pair<ll,ll> b){
        if(a.se!=b.se)
        return a.se<b.se;
        else
        return a.fi<b.fi;
}
//----------------------------------------------------------------------

//----------------------------------------------------------------------
int main(){
    cin.tie(0);
    ios::sync_with_stdio(false);
    //-------------------------------  
    //ll begin_time=clock();
    //-------------------------------
    int n,c;cin>>n>>c;
    int D[31][31];
    for(int i=0;i<c;i++){
        for(int j=0;j<c;j++){
            cin>>D[i][j];
        }
    }
    int C[510][510];
    for(int i=0;i<n;i++){
        for(int j=0;j<n;j++){
            cin>>C[i][j];
            C[i][j]--;
        }
    }
    ll ans=INF;
    V<Pin>V1,V2,V3;
    for(int d=0;d<3;d++){
        int minm=IINF;
        for(int i=0;i<c;i++){
            for(int x=0;x<n;x++){
                for(int y=0;y<n;y++){
                    if((x+1+y+1)%3==d){
                        tmp+=D[C[x][y]][i];
                    }
                }
            }
            if(d==0)V1.pb(mp(tmp,i));
            else if(d==1)V2.pb(mp(tmp,i));
            else V3.pb(mp(tmp,i));
        }
    }
    sort(all(V1));sort(all(V2));sort(all(V3));
    for(int i=0;i<c;i++){
        for(int j=0;j<c;j++){
            for(int k=0;k<c;k++){
                if(V1[i].se==V2[j].se||V1[i].se==V3[k].se||V3[k].se==V2[j].se){
                    continue;
                }
                chmin(ans,V1[i].fi+V2[j].fi+V3[k].fi);
            }
        }
    }
    cout<<ans<<Endl;
    //-------------------------------  
    //ll end_time=clock();cout<<"time="<<end_time-begin_time<<"ms"<<endl;
    //-------------------------------
    return 0;
}
//----------------------------------------------------------------------




































Compiler output:
a.cc: In function 'int main()':
a.cc:96:25: error: 'tmp' was not declared in this scope; did you mean 'tm'?
   96 |                         tmp+=D[C[x][y]][i];
      |                         ^~~
      |                         tm
a.cc:100:30: error: 'tmp' was not declared in this scope; did you mean 'tm'?
  100 |             if(d==0)V1.pb(mp(tmp,i));
      |                              ^~~
      |                              tm
a.cc:101:35: error: 'tmp' was not declared in this scope; did you mean 'tm'?
  101 |             else if(d==1)V2.pb(mp(tmp,i));
      |                                   ^~~
      |                                   tm
a.cc:102:27: error: 'tmp' was not declared in this scope; did you mean 'tm'?
  102 |             else V3.pb(mp(tmp,i));
      |                           ^~~
      |                           tm