#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 = 1000000000000000000;
long long sum, ans = 0, mx = 0, mn = 1000000000, num, pos;
/*
ViHHiPuh
(( `'-""``""-'` ))
)-__-_.._-__-(
/ --- (o _ o) --- \
\ .-* ( .0. ) *-. /
_'-. ,_ '=' _, .-'_
/ `;#'#'# - #'#'#;` \
\_)) -----'#'----- ((_/
# --------- #
'# ------- ------ #'
/..-'# ------- #'-.\
_\...-\'# -- #'/-.../_
((____)- '#' -(____))
cout << fixed << setprecision(6) << x;
ios_base::sync_with_stdio(0);
cin.tie(0); cout.tie(0);
freopen ( "sum.in", "r", stdin )
*/
struct Node {
int dp, u, pr, col;
};
struct cmp {
bool operator () ( const Node& a, const Node& b ) const {
if ( a.dp == b.dp ) {
if ( a.u == b.u ) {
if ( a.pr == b.pr ) {
return a.col < b.col;
}
return a.pr < b.pr;
}
return a.u < b.u;
}
return a.dp < b.dp;
}
};
int n, m, x, y, z[ 2001 ], t[ 2001 ];
int mp[ 2001 ][ 2001 ];
vector <pair<int, int> > v[ 2001 ];
int dp[ 2001 ][ 2001 ][ 2 ];
set <Node, cmp > st;
void dfs( int u, int pr, int col ) {
int num = 0;
int pos = 0;
if ( col == 1 ) {
for ( auto to : v[ u ] ) {
if ( to.first == pr )
num = t[ to.second ], pos = z[ to.second ];
}
}
int sum;
for ( auto to : v[ u ] ) {
if ( to.first == pr )
continue;
if ( z[ to.second ] == pos )
sum = num;
else
sum = 0;
if ( dp[ to.first ][ u ][ 1 ] > dp[ u ][ pr ][ col ] + t[ to.second ] ) {
dp[ to.first ][ u ][ 1 ] = dp[ u ][ pr ][ col ] + t[ to.second ];
dfs( to.first, u, 1 );
}
if ( dp[ to.first ][ u ][ 0 ] > dp[ u ][ pr ][ col ] + mp[ u ][ z[ to.second ] ] - t[ to.second ] - sum ) {
dp[ to.first ][ u ][ 0 ] = dp[ u ][ pr ][ col ] + mp[ u ][ z[ to.second ] ] - t[ to.second ] - sum;
dfs( to.first, u, 0 );
}
}
}
main () {
cin >> n >> m;
for ( int i = 1; i <= m; i ++ ) {
cin >> x >> y >> z[ i ] >> t[ i ];
mp[ x ][ z[ i ] ] += t[ i ];
mp[ y ][ z[ i ] ] += t[ i ];
v[ x ].push_back( { y, i } );
v[ y].push_back( { x, i } );
}
for ( int i = 2; i <= n; i ++ ) {
for ( int j = 1; j <= n; j ++ )
dp[ i ][ j ][ 1 ] = dp[ i ][ j ][ 0 ] = oo;
}
st.insert( { 0, 1, 0, 0 } );
while ( st.size() ) {
Node u = *st.begin();
st.erase( st.begin() );
num = pos = 0;
if ( u.col == 1 ) {
for ( auto to : v[ u.u ] ) {
if ( to.first == u.pr ) {
num = t[ to.second ], pos = z[ to.second ];
}
}
}
for ( auto to : v[ u.u ] ) {
if ( to.first == u.pr )
continue;
sum = 0;
if ( z[ to.second ] == pos )
sum = num;
if ( dp[ to.first ][ u.u ][ 1 ] > u.dp + t[ to.second ] ) {
st.erase( { dp[ to.first ][ u.u ][ 1 ], to.first, u.u, 1 } );
dp[ to.first ][ u.u ][ 1 ] = u.dp + t[ to.second ];
st.insert( { dp[ to.first ][ u.u ][ 1 ], to.first, u.u, 1 } );
}
if ( dp[ to.first ][ u.u ][ 0 ] > u.dp + mp[ u.u ][ z[ to.second ] ] - t[ to.second ] - sum ) {
st.erase( { dp[ to.first ][ u.u ][ 0 ], to.first, u.u, 0 } );
dp[ to.first ][ u.u ][ 0 ] = u.dp + mp[ u.u ][ z[ to.second ] ] - t[ to.second ] - sum;
st.insert( { dp[ to.first ][u.u ][ 0 ], to.first, u.u, 0 } );
}
}
}
mn = oo;
for ( int i = 1; i <= n; i ++ )
mn = min( mn, min( dp[ n ][ i ][ 1 ], dp[ n ][ i ][ 0 ] ) );
if ( mn == oo )
cout << "-1\n";
else
cout << mn << "\n";
}
