因为每行每列都需要是回文,所以四个角的数字必须相同。先考虑这四个数字,让它们都转变成某个数字,使得操作数最小,让它们都变成中位数是最优的。对于矩阵中所有的这样的四个数字都做这样的操作。实现的过程中需要考虑奇偶性。
// Date: Sun Dec 3 18:52:56 2023
#include <climits>
#include <cmath>
#include <cstdio>
#include <cstdlib>
#include <cstring>
#include <algorithm>
#include <functional>
#include <iomanip>
#include <iostream>
#include <map>
#include <queue>
#include <set>
#include <sstream>
#include <stack>
#include <string>
#include <utility>
#include <vector>
using namespace std;
const int INF = 0x3f3f3f3f, MOD = 1e9 + 7;
const double eps = 1e-8;
const int dir[8][2] = {
{0, 1}, {0, -1}, {1, 0}, {-1, 0}, {1, 1}, {1, -1}, {-1, 1}, {-1, -1},
};
typedef long long ll;
typedef unsigned long long ull;
typedef vector<int> VI;
typedef pair<int, int> PII;
const ull Pr = 131;
#define For(i, a, b) for (int i = int(a); i < int(b); ++i)
#define Rof(i, a, b) for (int i = int(b) - 1; i >= int(a); --i)
#define For1(i, a, b) for (int i = int(a); i <= int(b); ++i)
#define Rof1(i, a, b) for (int i = int(b); i >= int(a); --i)
#define ForE(i, j) for (int i = h[j]; i != -1; i = ne[i])
#define f1 first
#define f2 second
#define pb push_back
#define has(a, x) (a.find(x) != a.end())
#define nonempty(a) (!a.empty())
#define all(a) (a).begin(), (a).end()
#define SZ(a) int((a).size())
#ifdef _DEBUG
#define debug1(x) cout << #x " = " << x << endl;
#define debug2(x, y) cout << #x " = " << x << " " #y " = " << y << endl;
#define debug3(x, y, z) \
cout << #x " = " << x << " " #y " = " << y << " " #z " = " << z << endl;
#else
#define debug1
#define debug2
#define debug3
#endif
const int N = 110;
int t, n, m;
ll a[N][N];
bool vis[N][N];
int main(void) {
#ifdef _DEBUG
freopen("1422b.in", "r", stdin);
#endif
std::ios::sync_with_stdio(false);
cin.tie(NULL);
cout.tie(NULL);
cin >> t;
while (t--) {
cin >> n >> m;
memset(vis, false, sizeof vis);
For1(i, 1, n) {
For1(j, 1, m) { cin >> a[i][j]; }
}
ll res = 0;
For1(i, 1, n) {
int i1 = n + 1 - i;
if (i1 < i)
break;
For1(j, 1, m) {
VI tmp;
tmp.clear();
int j1 = m + 1 - j;
if (j1 < j)
break;
if (j1 != j) {
tmp.pb(a[i][j]);
tmp.pb(a[i][j1]);
if (i != i1) {
tmp.pb(a[i1][j]);
tmp.pb(a[i1][j1]);
}
} else {
if (i != i1) {
tmp.pb(a[i][j]);
tmp.pb(a[i1][j]);
}
}
int len = SZ(tmp);
if (len)
sort(all(tmp));
if (len == 4) {
For(k, 0, len) { res += abs(tmp[k] - tmp[1]); }
} else if (len == 2) {
res += abs(tmp[0] - tmp[1]);
}
}
}
cout << res << '\n';
}
return 0;
}