#include <iostream>
#include <bits/stdc++.h>
#include <cmath>
#include <algorithm>
#include <vector>
#include <deque>
#include <set>
#include <stack>
#include <string>
#include <map>
#include <queue>
#define int long long
#define sqrt sqrtl
using namespace std;
const long long oo = 1e18;
long long sum, ans = 0, mx = 0, mn = 1000000000, num, pos;
/*
ViHHiPuh
(( `'-""``""-'` ))
)-__-_.._-__-(
/ --- (o _ o) --- \
\ .-* ( .0. ) *-. /
_'-. ,_ '=' _, .-'_
/ `;#'#'# - #'#'#;` \
\_)) -----'#'----- ((_/
# --------- #
'# ------- ------ #'
/..-'# ------- #'-.\
_\...-\'# -- #'/-.../_
((____)- '#' -(____))
cout << fixed << setprecision(6) << x;
freopen ( "sum.in", "r", stdin )
*/
int n, m, x[ 200001 ], y[ 200001 ], z[ 200001 ], t[ 200001 ];
vector <pair<int, int> > v[ 100001 ];
map <int, int> mp[ 100001 ];
int d[ 100001 ];
set <pair<int, int> > st;
main () {
ios_base::sync_with_stdio(0);
cin.tie(0); cout.tie(0);
cin >> n >> m;
for ( int i = 1; i <= m; i ++ ) {
cin >> x[ i ] >> y[ i ] >> z[ i ] >> t[ i ];
mp[ x[ i ] ][ z[ i ] ] += t[ i ];
mp[ y[ i ] ][ z[ i ] ] += t[ i ];
}
for ( int i = 1; i <= m; i ++ ) {
v[ x[ i ] ].push_back( { y[ i ], min( mp[ x[ i ] ][ z[ i ] ] - t[ i ], t[ i ] ) } );
v[ y[ i ] ].push_back( { x[ i ], min( mp[ y[ i ] ][ z[ i ] ] - t[ i ], t[ i ] ) } );
}
for ( int i = 1; i <= n; i ++ )
d[ i ] = oo;
d[ 1 ] = 0;
st.insert( { 0, 1 } );
while ( st.size() ) {
int u = st.begin()->second;
st.erase( st.begin() );
for ( auto to : v[ u ] ) {
if ( d[ to.first ] > d[ u ] + to.second ) {
st.erase( { d[ to.first ], to.first } );
d[ to.first ] = d[ u ] + to.second;
st.insert( { d[ to.first ], to.first } );
}
}
}
if ( d[ n ] == oo )
cout << "-1";
else
cout << d[ n ];
}
/*
h[ i ] + i * 2 < h[ i + 1 ] + i * 2 + 4
h[ i ] - h[ i + 1 ] < 4
3 5 2 4 1
5 9 8 14 13
*/
