Problem7314--CodeChef FROGV - Chef and Frogs

7314: CodeChef FROGV - Chef and Frogs

[Creator : ]
Time Limit : 1.000 sec  Memory Limit : 256 MiB

Description

Nobody knows, but N frogs live in Chef's garden.
Now they are siting on the X-axis and want to speak to each other. One frog can send a message to another one if the distance between them is less or equal to K.
Chef knows all P pairs of frogs, which want to send messages. Help him to define can they or not!
Note : More than 1 frog can be on the same point on the X-axis.

Input

The first line contains three integers N, K and P.
The second line contains N space-separated integers $A_1, A_2, ..., A_N$ denoting the x-coordinates of frogs".
Each of the next P lines contains two integers A and B denoting the numbers of frogs according to the input.

Output

For each pair print "Yes" without a brackets if frogs can speak and "No" if they cannot.

Constraints

$1≤N,P≤10^5$
$0 \le A_i, K \le 10^9$
$1 \le A, B \le N$

Sample 1 Input

5 3 3
0 3 8 5 12
1 2
1 3
2 5

Sample 1 Output

Yes
Yes
No
For pair (1, 2) frog 1 can directly speak to the frog 2 as the distance between them is 3 - 0 = 3 \le K.
For pair (1, 3) frog 1 can send a message to frog 2, frog 2 can send it to frog 4 and it can send it to frog 3.
For pair (2, 5) frogs can't send a message under current constraints.

HINT

难度系数:1668
题目来源:CodeChef FROGV

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