题解 | #小美的蛋糕切割#

十年OI一场空，不开long long 见祖宗。

#include <iostream>
#include <queue>
#include <map>
#include <set>
#include <cmath>
#include <cstring>
#include <algorithm>
#include <iomanip>
#include <stack>
#include <numeric>
#include <ctime>
#include <string>
#include <bitset>
#include <unordered_map>
#include <unordered_set>

using namespace std;
using ll = long long;
const ll N = 1e3 + 5, mod = 1e9 + 7, inf = 2e18;

int n, m, q;
ll a[N][N];

void solve() {
    cin >> n >> m;

    for (int i = 1; i <= n; i++) {
        for (int j = 1; j <= m; j++) {
            cin >> a[i][j];
            a[i][j] += a[i - 1][j] + a[i][j - 1] - a[i - 1][j - 1];
        }
    }

    //遍历行
    ll ans = inf;
    for (int i = 1; i < m; i++) {
        ll x = a[n][i];
        ll y = a[n][m] - x;
        ans = min(ans, abs(x - y));
    }

    for (int i = 1; i < n; i++) {
        ll x = a[i][m];
        ll y = a[n][m] - x;
        ans = min(ans, abs(x - y));
    }

    cout << (ans == inf ? a[1][1] : ans);

}

int main() {
    ios::sync_with_stdio(0), cin.tie(0), cout.tie(0);

    int t = 1;
    //cin >> t;

    while (t--) {

        solve();

    }

    return 0;
}