#include <cstdio>
#include <iostream>
#include <cstring>
#include <string>
#include <cstdlib>
#include <algorithm>
#include <cmath>
#include <set>
#include <list>
#include <queue>
#include <map>
using namespace std;
#define L(i) i<<1
#define R(i) i<<1|1
#define INF 0x3f3f3f3f
#define pi acos(-1.0)
#define eps 1e-4
int n,m;
int a[1010][1010];
long long dp[1010][1010];
int main()
{
    while(scanf("%d%d",&n,&m) != EOF)
    {
        for(int i = 0; i < n; i++)
            for(int j = 0; j < m; j++)
                scanf("%d",&a[i][j]);
        memset(dp,0,sizeof(dp));
        dp[1][0] = a[0][0] * a[1][0];
        dp[0][1] = a[0][0] * a[0][1];
        for(int i = 3; i <= ((m-1)%2?m-1:m-2); i++)
            dp[0][i] = dp[0][i-2] + a[0][i-1] * a[0][i];
        for(int i = 3; i <= ((n-1)%2?n-1:n-2); i++)
            dp[i][0] = dp[i-2][0] + a[i-1][0] * a[i][0];
        for(int i = 1; i < n; i++)
            for(int j = 1; j < m; j++)
            if((i+j)%2)
        {
            dp[i][j] = min(a[i-1][j]*a[i][j],a[i][j-1]*a[i][j]) + dp[i-1][j-1];
            if(j > 1)
                dp[i][j] = min(a[i][j-1]*a[i][j]+dp[i][j-2],dp[i][j]);
            if(i > 1)
                dp[i][j] = min(a[i-1][j]*a[i][j]+dp[i-2][j],dp[i][j]);
        }
//        for(int i = 0; i < n; i++)
//            {for(int j = 0; j <m; j++)
//            printf("%d ",dp[i][j]);
//            printf("\n");
//            }

        printf("%d\n",dp[n-1][m-1]);
    }
    return 0;
}