Lennot

#!/usr/bin/env python
# -*- coding: utf-8 -*-

import sys
from sys import stdin
from sys import stdout

def readline():
    return stdin.readline().strip()

line1 = readline().split(' ')
# Kaupunkeja
n = int(line1[0])
# Lentoja
m = int(line1[1])
line1 = None

class Flight:
    def __init__(self, a, b, h):
        self.fr = a
        self.to = b
        self.price = int(h)

class City:
    def __init__(self, aid):
        self.total_price = sys.maxint
        self.calculated = False
        self.con_fr = []
        self.con_to = []
        self.stack = 0
        self.aid = aid
    def __eq__(self, other):
        return (isinstance(other, self.__class__)
            and self.aid == other.aid)


flights = []
cities = []
for c in range(n):
    cities.append(City(c))

uncalculated = list(cities)

for f in range(m):
    row = readline().split(' ')
    flight = Flight(cities[int(row[0])-1], cities[int(row[1])-1], row[2])
    flights.append(flight)
    flight.fr.con_to.append(flight)
    # flight.to.con_fr.append(flight)

start = cities[0]
end = cities[-1]
current = cities[0]

current.total_price = 0


found = False
while not found:
    if len(current.con_to) > 0:
        for flight in current.con_to:
            city = flight.to
            if not city.calculated:
                if current.stack % 2 == 0:
                    new_price = current.total_price + flight.price
                else:
                    new_price = current.total_price
                if new_price < city.total_price:
                    city.total_price = new_price
                    city.stack = current.stack + 1
    uncalculated.remove(current)
    current.calculated = True
    if current == end:
        found = True
        print(current.total_price)
        break
    
    smallest_price = sys.maxint
    for city in uncalculated:
        if city.total_price < smallest_price:
            smallest = city
            smallest_price = city.total_price
    
    current = smallest

Test 1

Group: 1

Verdict: WRONG ANSWER

Test 2

Group: 1

Verdict: ACCEPTED

Test 3

Group: 1

Verdict: ACCEPTED

Test 4

Group: 1

Verdict: ACCEPTED

Test 5

Group: 1

Verdict: ACCEPTED

Test 6

Group: 2

Verdict: WRONG ANSWER

Test 7

Group: 2

Verdict: WRONG ANSWER

Test 8

Group: 2

Verdict: WRONG ANSWER

Test 9

Group: 2

Verdict: WRONG ANSWER

Test 10

Group: 2

Verdict: WRONG ANSWER

Test 11

Group: 3

Verdict: RUNTIME ERROR

Test 12

Group: 3

Verdict: RUNTIME ERROR

Test 13

Group: 3

Verdict: RUNTIME ERROR

Test 14

Group: 3

Verdict: RUNTIME ERROR

Test 15

Group: 3

Verdict: RUNTIME ERROR

Test 16

Group: 3

Verdict: RUNTIME ERROR

Test 17

Group: 3

Verdict: RUNTIME ERROR