6759.Investigation

Time Limit: 1s Memory Limit: 512MB

You are going to travel from Syrjälä to Lehmälä by plane. You would like to find answers to the following questions:

  • what is the minimum price of such a route?
  • how many minimum-price routes are there? (modulo $10^9+7)$
  • what is the minimum number of flights in a minimum-price route?
  • what is the maximum number of flights in a minimum-price route?

Input Format(From the terminal/stdin)

The first input line contains two integers $n$ and $m$ : the number of cities and the number of flights. The cities are numbered $1,2,\ldots,n$ . City 1 is Syrjälä, and city $n$ is Lehmälä.

After this, there are $m$ lines describing the flights. Each line has three integers $a$ , $b$ , and $c$ : there is a flight from city $a$ to city $b$ with price $c$ . All flights are one-way flights.

You may assume that there is a route from Syrjälä to Lehmälä.

  • $1 \le n \le 10^5$
  • $1 \le m \le 2 \cdot 10^5$
  • $1 \le a,b \le n$
  • $1 \le c \le 10^9$

Output Format(To the terminal/stdout)

Print four integers according to the problem statement.

Sample Input

Copy
4 5
1 4 5
1 2 4
2 4 5
1 3 2
3 4 3
 · \n
 · · \n
 · · \n
 · · \n
 · · \n
 · · \n

Sample Output

Copy
5 2 1 2
 · · · \n
Source: CSES, Graph Algorithms, 1202

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