#include<iostream>
#include<cmath>
#include<iomanip>

using namespace std;



#define Type int
const int  maxint = 30000;

int Dijkstra(int n, int v, int m, Type **c, int rank[])
{
	bool s[maxint];
	int i,j,u, temp, *dist, **pre,min;
	dist = new int [n+1];
	pre = new int *[n+1];
	for(i=0; i<=n; i++)
		pre[i] = new int [2];
	Type newdist;
	for(i=1; i<=n; i++)
	{
		dist[i]=c[v][i]; //第1点到第i点的距离
		s[i]=false;
		pre[i][0]=pre[i][1]=rank[i]; //pre[i][0],pre[i][1]分别存储第1点到第i点的最高等级  和最低等级
	}
	dist[v]=0; s[v]=true;

	for(i=1; i < n; i++)
	{
		temp = maxint;
		u = v;
		for(j=1; j<=n;j++)
			if(!s[j] && (dist[j]<temp)) 
			{
				u = j;
				temp = dist[j];
			}
		s[u]=true;

		for(j=1; j<=n;j++)
			if(!s[j] && (c[u][j]< maxint) && abs(pre[u][0]-rank[j])<=m
				         && abs(pre[u][1]-rank[j])<=m)
			{
				newdist=dist[u]+c[u][j];
				if(newdist < dist[j])
				{
					dist[j] = newdist;
					pre[j][0] = pre[u][0]<rank[j]?pre[u][0]:rank[j];
					pre[j][1] = pre[u][1]>rank[j]?pre[u][1]:rank[j];
				}
			}
	}
	min = dist[1]+c[0][1];
	for(i=2; i<=n; i++)
		if(min>dist[i]+c[0][i]) min=dist[i]+c[0][i];
	return min;

}


int main()
{
	int m,n,value,num,*rank,i,j,a,b;
	int **c;
	cin>>m>>n;
	c = new int *[n+1];
	rank = new int [n+1];
	for(i=0; i<=n;i++)
		c[i] = new int [n+1];
	for(i=0; i<=n;i++)
		for(j=0; j<=n;j++)
			c[i][j] = maxint;
		
	for(i=1; i<=n;i++)
	{
		cin>>value>>rank[i]>>num;
		c[0][i]=value;
																														
		for(j=0; j<num; j++)
		{
			cin>>a>>b;
			c[i][a]=b;
			c[a][i]=b;
		}
	}

	
	cout<<Dijkstra(n, 1, m, c, rank)<<endl;

	delete []rank;
	for(i=0; i<=n;i++) delete []c[i];
	delete c;

	return 0;
}