SHPATH - The Shortest Path


You are given a list of cities. Each direct connection between two cities has its transportation cost (an integer bigger than 0). The goal is to find the paths of minimum cost between pairs of cities. Assume that the cost of each path (which is the sum of costs of all direct connections belongning to this path) is at most 200000. The name of a city is a string containing characters a,...,z and is at most 10 characters long.

Input

 

s [the number of tests <= 10]
n [the number of cities <= 10000]
NAME [city name]
p [the number of neighbours of city NAME]
nr cost [nr - index of a city connected to NAME (the index of the first city is 1)]
           [cost - the transportation cost]
r [the number of paths to find <= 100]
NAME1 NAME2 [NAME1 - source, NAME2 - destination]
[empty line separating the tests]

 

Output

 

cost [the minimum transportation cost from city NAME1 to city NAME2 (one per line)]

 

Example

 

Input:
1
4
gdansk
2
2 1
3 3
bydgoszcz
3
1 1
3 1
4 4
torun
3
1 3
2 1
4 1
warszawa
2
2 4
3 1
2
gdansk warszawa
bydgoszcz warszawa

Output:
3
2

 

Warning: large Input/Output data, be careful with certain languages


hide comments
yaseenmollik: 2020-10-21 10:30:39

AC in one go! Easy problem. Just store these strings into a map and implement standard Dijkstra algorithm.

abhinav18: 2020-08-17 18:57:00

Naive Dijkstra->TLE, Dijkstra on sparse graphs->AC. ;)

coolboy7: 2020-07-17 14:04:33

if you are getting tle after every possible optimization, check if you have forgetten to clear your adajency list after each test case.

sarthak_19: 2020-07-10 10:34:03

Use Priority Queue,Set Costed me 6 TLE

Last edit: 2020-07-10 10:34:21
soub5184: 2020-04-29 22:42:25

std::set is a f**king bit*h, priority_queue to the rescue

sangmai: 2019-12-31 12:49:16

After I switch to directed graph I got AC with 0.57 sec.
Undirected graph gives 1.4 sec :(

Last edit: 2019-12-31 12:49:30
sangmai: 2019-12-30 15:08:39

Why are people using directed graph? The problem statement does not say that. Does it affect the correctness of the program?

abhishek_chn: 2019-10-23 19:47:05

AC in 0.39 secs :P
Did in C lang

ankitsinha3005: 2019-08-23 19:44:41

Was Getting a TLE just because i was using map ,Dont forget to use unordered_map

importme: 2019-07-20 17:14:18

can we consider that the cities asked are connected


Added by:Darek Dereniowski
Date:2004-05-10
Time limit:1.5s
Source limit:50000B
Memory limit:1536MB
Cluster: Cube (Intel G860)
Languages:All
Resource:DASM Programming League 2003 (problemset 11)