#include<iostream>
#include<math.h>
using namespace std;

const int N = 101;
const long infinit = 4000000;




typedef struct Money
{
	 long  P;
		int L,X;
}Money;



Money money[N];

bool ttry(int path[],int w,int n,int m)
{
       int t;
	while(w > 0)
	 {
	t = abs(money[w].L-money[n].L);
     if (t>m)
	 {
      return false;
	 }
	 w = path[w];
	 }
	return true;
}

int main()
{

	long G[N][N]; 
	int i,j,m,n,t1,t2,min,w,h;
	int mark[N],d[N],path[N];
	
     while(cin >> m >> n)
	 {
          for ( i = 1; i <= n ; i++)
		  {
			  path[i] = 1;
			  d[i] = infinit;
			  mark[i] = 0;
		  }
		    path[1] = 0;
           
	 for ( i = 1; i <= n; i++)
		 for (j = 1; j<= n; j++)
		 {
		G[i][j] = infinit;
		if (i==j)
		{
			G[i][j] = 0;
		}
		 }
	
		 
	 for (i = 1; i <= n; i++)
	 {
		 cin >> money[i].P;
		 cin >> money[i].L;
		 cin >> money[i].X;
		 for (j = 1; j<= money[i].X;j++)
		 {
			 cin >> t1;
			 cin >> t2;
			 G[i][t1] = t2;
		  	 //G[t1][i] = t2;
		 }
	 }

  
        for (i = 1;i <= n; i++)
			if (G[1][i]!=infinit&&ttry(path,1,i,m)==true)
			{
			d[i] = G[1][i]+money[i].P;
			}
		
             mark[1] = 1;
		for (i = 2; i <= n; i++)
		{
		 min = infinit;
		 w = 1;
		  for (j = 2; j <= n; j++)
			if (mark[j]==0&&min>d[j])
			{
               min = d[j];
			   w = j;
			}
			mark[w] = 1;
		
			for (j = 1; j <= n; j++)
			   if(ttry(path,w,j,m)==true)
			 if (mark[j]==0&&G[w][j]<infinit&&(d[j]>d[w]-money[w].P+G[w][j]+money[j].P))
			 {
                 d[j] = d[w]-money[w].P+G[w][j]+money[j].P;	
				 path[j] = w;
			 }
			 
		}
	
		for(i = 2; i <= n; i++)
			if (d[i]<d[1])
			{
		
				d[1] = d[i];
			}
		
		
			cout << d[1] ;
            
	 }
return 0;

}