TRAFFICN - Traffic Network

The city traffic network consists of n nodes numbered from 1 to n and m one-way roads connecting pairs of nodes. In order to reduce the length of the shortest path between two different critical nodes s and t, a list of k two-way roads are proposed as candidates to be constructed. Your task is to write a program to choose one two-way road from the proposed list in order to minimize the resulting shortest path between s and t.


The input file consists of several data sets. The first line of the input file contains the number of data sets which is a positive integer and is not bigger than 20. The following lines describe the data sets.

For each data set, the first line contains five positive integers n (n ≤ 10 000), m (m ≤ 100 000), k (k < 300), s (1 ≤ s ≤ n), t (1 ≤ t ≤ n) separated by space. The ith line of the following m lines contains three integers di, ci, li separated by space, representing the length li ( 0< li ≤ 1000) of the ith one-way road connecting node di to ci. The jth line of the next k lines contains three positive integers uj, vj and qj (qj ≤ 1000) separated by space, representing the jth proposed two-way road of length qj connecting node uj to vj.


For each data set, write on one line the smallest possible length of the shortest path after building the chosen one two-way road from the proposed list. In case, there does not exist a path from s to t, write -1.


Sample Input
4 5 3 1 4
1 2 13
2 3 19
3 1 25
3 4 17
4 1 18
1 3 23
2 3 5
2 4 25	

Sample Output

hide comments
peeyush taneja: 2015-07-26 22:01:44

Finally AC

Dhruv Mullick: 2015-05-29 16:40:52

The question should rather read "write a program to choose at most one two-way road".

KESHAV BANSAL: 2015-01-31 07:58:17

tle while using scanf
WA if using INT_MAX
Finally AC by reading Comments :P
use fast i/o and use 1061109567 instead of INT_MAX

AlcatraZ: 2015-01-22 20:42:18

For my algo, INT_MAX is working fine ..But if you are adding anything to INT_MAX you will get an integer overflow..

Last edit: 2015-01-25 22:14:55
Pranav Vaish: 2014-12-10 23:54:03

Very tight time constraints. Had to optimize a lot!. Please increase the time to 2 seconds at least.

ABHISHEK004: 2014-10-24 18:47:33

@Archit Jain
don't understand why wrong answer using INT_MAX, but accepted using INF as 1061109567

___Durgesh___: 2014-09-24 12:29:01

whts wrong wid cin & cout getting tle &
got accepted using fast input
huge memory difference :P:P with previous one(tle) .. anyone please explain my doubt ..m not getting !!

Last edit: 2014-09-24 12:30:32
||N0VICE||: 2014-08-12 19:52:59

finally accepted after tonnes of WAs

Dario Sindicic: 2014-08-02 15:16:15

200th learn new dijkstra

Archit Jain: 2014-07-21 22:38:43

assign INF as 1061109567 then AC
else if u are using INT_MAX then wa

Last edit: 2014-07-21 22:38:57

Added by:Duc
Time limit:0.140s
Source limit:50000B
Memory limit:1536MB
Cluster: Cube (Intel G860)
Languages:All except: ERL JS-RHINO NODEJS PERL6 VB.NET
Resource:ACM Regional, Ho Chi Minh City 2008