#include <map>
#include <set>
#include <stack>
#include <queue>
#include <cmath>
#include <ctime>
#include <vector>
#include <cstdio>
#include <cctype>
#include <cstring>
#include <cstdlib>
#include <iostream>
#include <algorithm>
using namespace std;
#define INF 0x3f3f3f3f
#define inf -0x3f3f3f3f
#define lson l,m,rt<<1
#define rson m+1,r,rt<<1|1
#define mem0(a) memset(a,0,sizeof(a))
#define mem1(a) memset(a,-1,sizeof(a))
#define mem(a, b) memset(a, b, sizeof(a))
int mp[1010][1010];
int dp[1010][1010];

int main(){
    int n,m;
    while(scanf("%d%d",&n,&m)!=EOF){
        for(int i=1;i<=n;i++)
            for(int j=1;j<=m;j++){
                scanf("%d",&mp[i][j]);
                dp[i][j]=INF;
            }
        for(int i=1;i<=n;i++)
            for(int j=1;j<=m;j++){
                if(i==1&&j==1){
                    dp[i][j]=0;
                }
                else if(i==1){
                    if((i+j)%2==1){
                        dp[i][j]=dp[i][j-1]+mp[i][j-1]*mp[i][j];
                    }
                    else
                        dp[i][j]=dp[i][j-1];
                }
                else if(j==1){
                    if((i+j)%2==1){
                        dp[i][j]=dp[i-1][j]+mp[i-1][j]*mp[i][j];
                    }
                    else
                        dp[i][j]=dp[i-1][j];
                }
                else{
                    if((i+j)%2==1){
                        dp[i][j]=min(dp[i-1][j]+mp[i-1][j]*mp[i][j],dp[i][j-1]+mp[i][j-1]*mp[i][j]);
                    }
                    else
                        dp[i][j]=min(dp[i-1][j],dp[i][j-1]);
                }
            }
        printf("%d\n",dp[n][m]);
    }
    return 0;
}