#include<bits/stdc++.h>
using namespace std;
#define inf 0x3f3f3f3f
int e[25][15];
int dp[25][15];
int main()
{
int n,m,i,j,k;
while(cin>>n>>k){memset(dp,inf,sizeof(dp));
for(i=1;i<=k;++i) dp[1][i]=0;
for(i=n;i>=1;--i)
for(j=1;j<=k;++j)
scanf("%d",&e[i][j]);
for(i=2;i<=n;++i){
for(m=1;m<=k;++m){
for(j=1;j<=k;++j){
dp[i][m]=min(dp[i][m],abs(e[i-1][j]-e[i][m])+dp[i-1][j]);
}
}
}
int ans=inf;
for(i=1;i<=k;++i) ans=min(ans,dp[n][i]);
cout<<ans<<endl;
}
return 0;
}