Score : $500$ points
We have a simple undirected graph with $N$ vertices and $M$ edges. The vertices are numbered $1,\ldots,N$. For each $i=1,\ldots,M$, the $i$-th edge connects Vertex $a_i$ and Vertex $b_i$. Additionally, the degree of each vertex is at most $3$.
For each $i=1,\ldots,Q$, answer the following query.
Input is given from Standard Input in the following format:
$N$ $M$ $a_1$ $b_1$ $\vdots$ $a_M$ $b_M$ $Q$ $x_1$ $k_1$ $\vdots$ $x_Q$ $k_Q$
Print $Q$ lines. The $i$-th line should contain the answer to the $i$-th query.
6 5 2 3 3 4 3 5 5 6 2 6 7 1 1 2 2 2 0 2 3 4 1 6 0 4 3
1 20 2 20 7 6 20
For the $1$-st query, the only vertex whose distance from Vertex $1$ is at most $1$ is Vertex $1$, so the answer is $1$.
For the $2$-nd query, the vertices whose distances from Vertex $2$ are at most $2$ are Vertex $2$, $3$, $4$, $5$, and $6$, so the answer is their sum, $20$.
The $3$-rd and subsequent queries can be answered similarly.