#include<cstdio>
#include<cstring>
#include<algorithm>
using namespace std;
const int inf=0x3f3f3f3f;
int n,m,S,T,a[110];
namespace nwf{const int maxn=20010,maxm=40010;int tot=1,first[maxn],d[maxn],q[maxn],cur[maxn];struct edge{int v,f,from;}e[maxm*2];void insert(int u,int v,int f){tot++;e[tot].v=v;e[tot].f=f;e[tot].from=first[u];first[u]=tot;tot++;e[tot].v=u;e[tot].f=0;e[tot].from=first[v];first[v]=tot;}bool bfs(){memset(d,-1,sizeof(d));d[S]=0;int head=0,tail=1;q[head]=S;while(head<tail){int x=q[head++];for(int i=first[x];i;i=e[i].from)if(e[i].f&&d[e[i].v]==-1){d[e[i].v]=d[x]+1;q[tail++]=e[i].v;}}return ~d[T];}int dfs(int x,int a){if(x==T||a==0)return a;int flow=0,f;for(int& i=cur[x];i;i=e[i].from)if(e[i].f&&d[e[i].v]==d[x]+1&&(f=dfs(e[i].v,min(a,e[i].f)))){e[i].f-=f;e[i^1].f+=f;flow+=f;a-=f;if(a==0)break;}return flow;}int dinic(){int ans=0;while(bfs()){for(int i=S;i<=T;i++)cur[i]=first[i];ans+=dfs(S,inf);}return ans;}
}
int main(){scanf("%d%d",&n,&m);for(int i=1;i<=n;i++)scanf("%d",&a[i]);S=0;T=n*n+1001;int ans=0;for(int i=1;i<=n;i++){for(int j=i;j<=n;j++){int u;scanf("%d",&u);if(i!=j){nwf::insert((i-1)*n+j,i*n+j,inf),nwf::insert((i-1)*n+j,(i-1)*n+j-1,inf);if(u>0)nwf::insert(S,(i-1)*n+j,u),ans+=u;else nwf::insert((i-1)*n+j,T,-u);//
            }else if(u-a[i]>0)nwf::insert(S,(i-1)*n+j,u-a[i]),ans+=u-a[i];else nwf::insert((i-1)*n+j,T,a[i]-u);}}for(int i=1;i<=1000;i++){nwf::insert(n*n+i,T,i*i*m);for(int j=1;j<=n;j++)if(a[j]==i)nwf::insert((j-1)*n+j,n*n+i,inf);}printf("%d",ans-nwf::dinic());return 0;
}