#include <cstdio>
#include <cstring>
#include <queue>
#define inf 0x3f3f3f3f
using namespace std;
queue<int> q;
int n , m , map[610][610] , w[610] , rd[610] , flag[610];
int head[610] , to[400000] , val[400000] , next[400000] , cnt = 1 , s , t , dis[610];
void init()
{
    int i , j;
    for(i = 1 ; i <= n * m ; i ++ )
        for(j = 1 ; j <= n * m ; j ++ )
            if(map[i][j])
                rd[j] ++ ;
    for(i = 1 ; i <= n * m ; i ++ )
        if(!rd[i])
            q.push(i);
    while(!q.empty())
    {
        i = q.front() , q.pop() , flag[i] = 1;
        for(j = 1 ; j <= n * m ; j ++ )
        {
            if(map[i][j])
            {
                rd[j] -- ;
                if(!rd[j]) q.push(j);
            }
        }
    }
}
void add(int x , int y , int z)
{
    to[++cnt] = y , val[cnt] = z , next[cnt] = head[x] , head[x] = cnt;
    to[++cnt] = x , val[cnt] = 0 , next[cnt] = head[y] , head[y] = cnt;
}
bool bfs()
{
    int x , i;
    while(!q.empty()) q.pop();
    memset(dis , 0 , sizeof(dis));
    dis[s] = 1 , q.push(s);
    while(!q.empty())
    {
        x = q.front() , q.pop();
        for(i = head[x] ; i ; i = next[i])
        {
            if(val[i] && !dis[to[i]])
            {
                dis[to[i]] = dis[x] + 1;
                if(to[i] == t) return 1;
                q.push(to[i]);
            }
        }
    }
    return 0;
}
int dinic(int x , int low)
{
    if(x == t) return low;
    int temp = low , i , k;
    for(i = head[x] ; i ; i = next[i])
    {
        if(val[i] && dis[to[i]] == dis[x] + 1)
        {
            k = dinic(to[i] , min(temp , val[i]));
            if(!k) dis[to[i]] = 0;
            val[i] -= k , val[i ^ 1] += k;
            if(!(temp -= k)) break;
        }
    }
    return low - temp;
}
void dfs(int x)
{
	int i;
	for(i = 1 ; i <= n * m ; i ++ )
		if(map[x][i] && flag[i])
			flag[i] = 0 , dfs(i);
}
int main()
{
    int i , j , k , x , y , ans = 0;
    scanf("%d%d" , &n , &m);
    s = 0 , t = n * m + 1;
    for(i = 1 ; i <= n ; i ++ )
    {
        for(j = 1 ; j <= m ; j ++ )
        {
            scanf("%d%d" , &w[(i - 1) * m + j] , &k);
            if(j > 1) map[(i - 1) * m + j][(i - 1) * m + j - 1] = 1;
            while(k -- ) scanf("%d%d" , &x , &y) , map[(i - 1) * m + j][x * m + y + 1] = 1;
        }
    }
    init();
    for(i = 1 ; i <= n * m ; i ++ )
    	if(!flag[i])
    		dfs(i);
    for(i = 1 ; i <= n * m ; i ++ )
    {
        if(flag[i])
        {
            if(w[i] >= 0) add(s , i , w[i]) , ans += w[i];
            else add(i , t , -w[i]);
            for(j = 1 ; j <= n * m ; j ++ )
                if(map[j][i] && flag[j])
                    add(i , j , inf);
        }
    }
    while(bfs()) ans -= dinic(s , inf);
    printf("%d\n" , ans);
    return 0;
}