program ss;
type thing=record
           p,l,x:longint;
           end;

var a:array[1..100] of thing;
    dist:array[1..100] of longint;
    hash:array[1..100] of boolean;
    map:array[1..100,1..100] of longint;
    can:array[1..100] of boolean;
    i,j,k,m,n,s,t,x,y,z,min,ans,l:longint;

begin
readln(m,n);
for i:=1 to n do
    for j:=1 to n do map[i,j]:=1000000000;
for i:=1 to n do
    begin
    readln(a[i].p,a[i].l,a[i].x);
    for j:=1 to a[i].x do
        begin
        readln(y,z); map[i,y]:=z;
        end;
    end;
if a[1].x=0 then begin writeln(a[1].p); halt; end;
ans:=1000000000;
for i:=1 to n do
    begin
    if not ((a[1].l>=a[i].l-m) and (a[1].l<=a[i].l)) then continue;
    s:=0;
    fillchar(can,sizeof(can),false);
    fillchar(hash,sizeof(hash),false);
    for j:=1 to n do
        if (a[j].l>=a[i].l-m) and (a[j].l<=a[i].l) then
           begin
           inc(s); can[j]:=true;
           end;
    hash[1]:=true;
    for j:=1 to n do
        if can[j] then dist[j]:=map[1,j];
    for l:=1 to s-1 do
        begin
        min:=1000000000;
        for j:=1 to n do
            if can[j] and (not hash[j]) and (dist[j]<min) then
               begin
               min:=dist[j];
               k:=j;
               end;
        hash[k]:=true;
        for j:=1 to n do
            if can[j] and (not hash[j]) and (dist[j]>dist[k]+map[k,j]) then
               dist[j]:=dist[k]+map[k,j];
        end;
    for j:=1 to n do
        if can[j] and (ans>dist[j]+a[j].p) then ans:=dist[j]+a[j].p;
    end;
if a[1].p>ans then writeln(ans) else writeln(a[1].p);
end.