#include<algorithm>
#include<iostream>
#include<cstring>
#include<cctype>
#include<cstdio>
#include<vector>
#include<queue>
#include<cmath>
using namespace std;
typedef long long ll;
const int N=705;
const int M=800005;
const int INF=1e9;
inline int read(){int X=0,w=0;char ch=0;while(!isdigit(ch)){w|=ch=='-';ch=getchar();}while(isdigit(ch))X=(X<<3)+(X<<1)+(ch^48),ch=getchar();return w?-X:X;
}
struct node{int nxt,to,w;
}edge[M];
int head[N],cnt=-1,S,T;
void add(int u,int v,int w){edge[++cnt].to=v;edge[cnt].w=w;edge[cnt].nxt=head[u];head[u]=cnt;
}
int lev[N],cur[N],dui[N];
bool bfs(int m){int r=0;for(int i=1;i<=m;i++){lev[i]=-1;cur[i]=head[i];}dui[0]=S,lev[S]=0;int u,v;for(int l=0;l<=r;l++){u=dui[l];for(int e=head[u];e!=-1;e=edge[e].nxt){v=edge[e].to;if(edge[e].w>0&&lev[v]==-1){ lev[v]=lev[u]+1;r++;dui[r]=v; if(v==T)return 1; }}}return 0;
}
int dinic(int u,int flow,int m){if(u==m)return flow;int res=0,delta;for(int &e=cur[u];e!=-1;e=edge[e].nxt){int v=edge[e].to;if(edge[e].w>0&&lev[u]<lev[v]){ delta=dinic(v,min(edge[e].w,flow-res),m); if(delta>0){edge[e].w-=delta;edge[e^1].w+=delta;res+=delta;if(res==flow)break; }}}if(res!=flow)lev[u]=-1;return res;
}
int n,m,ans,s[N],indeg[N];
queue<int>q;
void Topu(){for(int i=1;i<=n*m;i++){if(!indeg[i])q.push(i);}while(!q.empty()){int u=q.front();q.pop();for(int i=head[u];i!=-1;i=edge[i].nxt){if(!(i&1))continue;int v=edge[i].to;indeg[v]--;if(!indeg[v])q.push(v);}}for(int i=1;i<=n*m;i++){if(indeg[i]){s[i]=-INF;}}
}
int main(){memset(head,-1,sizeof(head));n=read(),m=read();S=n*m+1,T=S+1;for(int i=1;i<=n;i++){for(int j=1;j<=m;j++){int now=(i-1)*m+j;s[now]=read();int w=read();for(int k=1;k<=w;k++){int x=read()+1,y=read()+1;int bef=(x-1)*m+y;add(bef,now,INF);add(now,bef,0);indeg[bef]++;}if(j!=m){int bef=now+1;add(now,bef,INF);add(bef,now,0);indeg[now]++;}}}Topu();for(int i=1;i<=n*m;i++){if(s[i]>=0){ans+=s[i];add(S,i,s[i]);add(i,S,0);}else{add(i,T,-s[i]);add(T,i,0);}}while(bfs(T))ans-=dinic(S,INF,T);printf("%d\n",ans);return 0;
}