// bzoj1565

#include<algorithm>

#include<iostream>

#include<cstdlib>

#include<cstring>

#include<cstdio>

#include<cmath>

#include<queue>

#define LL long long

#define inf (1ll<<30)

#define free(a) freopen(a".in","r",stdin),freopen(a".out","w",stdout)

using namespace std;

const int maxn=100010,maxm=1000010;

int head[maxn],d[maxn],n,m,cnt,ans,tot,S,T;

int size[maxn],dfn[maxn],low[maxn],bel[maxn],vis[maxn],val[maxn],st[maxn],DFN,scc,top;

struct edge {int to,next,w;}e[maxm];

pair<int,int> E[maxm];

namespace Dinic {

	void link(int u,int v,int w) {

		e[++cnt]=(edge){v,head[u],w};head[u]=cnt;

		e[++cnt]=(edge){u,head[v],0};head[v]=cnt;

	}

	bool bfs() {

		for (int i=S;i<=T;i++) d[i]=-1;

		queue<int> q;q.push(S);d[S]=0;

		while (!q.empty()) {

			int x=q.front();q.pop();

			for (int i=head[x];i;i=e[i].next)

				if (e[i].w && d[e[i].to]<0) d[e[i].to]=d[x]+1,q.push(e[i].to);

		}

		return d[T]>0;

	}

	int dfs(int x,int f) {

		if (x==T || f==0) return f;

		int w,used=0;

		for (int i=head[x];i;i=e[i].next) if (e[i].w && d[e[i].to]==d[x]+1) {

				w=dfs(e[i].to,min(e[i].w,f-used));

				used+=w,e[i].w-=w;e[i^1].w+=w;

				if (used==f) return used;

			}

		if (!used) d[x]=-1;

		return used;

	}

	int main() {

		int flow=0;

		while (bfs()) flow+=dfs(S,inf);

		return flow;

	}

}

void link(int u,int v) {e[++cnt]=(edge){v,head[u]};head[u]=cnt;}

void Tarjan(int x) {

	st[++top]=x;dfn[x]=low[x]=++DFN;

	for (int i=head[x];i;i=e[i].next) {

		if (!dfn[e[i].to]) {

			Tarjan(e[i].to);

			low[x]=min(low[x],low[e[i].to]);

		}

		else if (!bel[e[i].to]) low[x]=min(low[x],dfn[e[i].to]);

	}

	if (dfn[x]==low[x]) {

		scc++;

		for (;st[top]!=x;top--) bel[st[top]]=scc,size[scc]++;

		bel[st[top--]]=scc;size[scc]++;

	}

}

bool dfs(int x) {

	if (vis[x]) return size[x];

	if (size[x]>1) size[x]=0;

	vis[x]=1;

	for (int i=head[x];i;i=e[i].next) if (e[i].w) size[x]&=dfs(e[i].to);

	return size[x];

}

int main() {

	scanf("%d%d",&n,&m);

	for (int i=0;i<n;i++)

		for (int x,y,t,j=1;j<=m;j++) {

			scanf("%d%d",&val[i*m+j],&t);

			for (int k=1;k<=t;k++) scanf("%d%d",&x,&y),link(x*m+y+1,i*m+j);

			if (j<m) link(i*m+j,i*m+j+1);

		}

	for (int i=1;i<=n*m;i++) if (!dfn[i]) Tarjan(i);

	for (int i=1;i<=n*m;i++)

		for (int j=head[i];j;j=e[j].next)

			if (bel[i]!=bel[e[j].to]) E[++tot]=pair<int,int>(bel[i],bel[e[j].to]);

	memset(head,0,sizeof(head));cnt=1;

	for (int i=1;i<=tot;i++) Dinic::link(E[i].first,E[i].second,inf);

	for (int i=1;i<=scc;i++) if (!vis[i]) dfs(i);

	S=0,T=n*m+1;

	for (int i=1;i<=n*m;i++) if (size[bel[i]]) {

			if (val[i]>=0) Dinic::link(S,bel[i],val[i]),ans+=val[i];

			else Dinic::link(bel[i],T,-val[i]);

		}

	ans=max(0,ans-Dinic::main());

	printf("%d",ans);

	return 0;

}