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#include <iostream>
#include <vector>
#include <algorithm>
#include <set>
#include <cmath>
#include <map>
#include <cstring>
using namespace std;
int n, m;
int mat[105][16];
int dp[105][1 << 15];
int rec(int at, int bitmask) {
    if(__builtin_popcount(bitmask) == m) {
        return 0;
    }
    if(at == n) {
        return 1e9;
    }
    if(dp[at][bitmask] != -1) {
        return dp[at][bitmask];
    }
    int result = 1e9;
    
    for(int i = 0; i < m; i++) {
        if((bitmask & (1 << i)) == 0) {
            int new_mask = bitmask | (1 << i);
            result = min(result, rec(at + 1, new_mask) + mat[at][i]);
        }
    }
    result = min(result, rec(at + 1, bitmask));
    return dp[at][bitmask] = result;
}
int main() {
    cin >> n >> m;
    vector<int> cost(m, 0);
    for(int i = 0; i < n; i++) {
        for(int j = 0; j < m; j++) {
            cin >> mat[i][j];
            cost[j] += mat[i][j];
        }
    }
    memset(dp, -1, sizeof dp);
    for(int i = 0; i < n; i++) {
        for(int j = 0; j < m; j++) {
            mat[i][j] = cost[j] - mat[i][j];
        }
    }
    cout << rec(0, 0) << endl;
    return 0;
}