bujxbeujbgjuwb

#include<iostream>
#include<cstring>
using namespace std;
const int N=205;
long long a[N][N],dp[N][N];
int main(){
int n,m;
cin>>n>>m;
for(int i=1;i<=n;i++)
for(int j=1;j<=m;j++)
cin>>a[i][j];
for(int i=1;i<=n;i++){
for(int j=1;j<=m;j++){
dp[i][j]=max(max(dp[i-1][j-1],dp[i-1][j]),dp[i-1][j+1])+a[i][j];
}
}
cout<<max(max(dp[n][m/2],dp[n][m/2+1]),dp[n][m/2+2]);
return 0;
}