7571: [CSES Problem Set] Shortest Routes II
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Description
There are $n$ cities and $m$ roads between them.
Your task is to process $q$ queries where you have to determine the length of the shortest route between two given cities.
Your task is to process $q$ queries where you have to determine the length of the shortest route between two given cities.
Input
The first input line has three integers $n, m, q$: the number of cities, roads, and queries.
Then, there are mm lines describing the roads. Each line has three integers $a, b, c$: there is a road between cities $a$ and $b$ whose length is $c$. All roads are two-way roads.
Finally, there are $q$ lines describing the queries. Each line has two integers $a$ and $b$: determine the length of the shortest route between cities $a$ and $b$.
Then, there are mm lines describing the roads. Each line has three integers $a, b, c$: there is a road between cities $a$ and $b$ whose length is $c$. All roads are two-way roads.
Finally, there are $q$ lines describing the queries. Each line has two integers $a$ and $b$: determine the length of the shortest route between cities $a$ and $b$.
Output
Print the length of the shortest route for each query. If there is no route, print $-1$ instead.
Constraints
$1≤n≤500
$1 \le m \le n^2$
$1 \le q \le 10^5$
$1 \le a,b \le n$
$1 \le c \le 10^9$
$1 \le m \le n^2$
$1 \le q \le 10^5$
$1 \le a,b \le n$
$1 \le c \le 10^9$
Sample 1 Input
4 3 5
1 2 5
1 3 9
2 3 3
1 2
2 1
1 3
1 4
3 2
Sample 1 Output
5
5
8
-1
3