Codeforces Beta Round 77 (Div. 2 Only)
E
Horse Races
Codeforces
未评级
原题
← D→
翻译中…

Petya likes horse racing very much. Horses numbered from $*l*$ to $*r*$ take part in the races. Petya wants to evaluate the probability of victory; for some reason, to do that he needs to know the amount of nearly lucky horses' numbers. A nearly lucky number is an integer number that has at least two lucky digits the distance between which does not exceed $*k*$. Petya learned from some of his mates from Lviv that lucky digits are digits $4$ and $7$. The distance between the digits is the absolute difference between their positions in the number of a horse. For example, if $*k* = 2$, then numbers $412395497$, $404$, $4070400000070004007$ are nearly lucky and numbers $4$, $4123954997$, $4007000040070004007$ are not.

翻译中…

Petya prepared $*t*$ intervals $[*l*_{*i*}, *r*_{*i*}]$ and invented number $*k*$, common for all of them. Your task is to find how many nearly happy numbers there are in each of these segments. Since the answers can be quite large, output them modulo $1000000007$ ($10^{9} + 7$).

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Input

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The first line contains two integers $*t*$ and $*k*$ ($1 ≤ *t*, *k* ≤ 1000$) — the number of segments and the distance between the numbers correspondingly. Next $*t*$ lines contain pairs of integers $*l*_{*i*}$ and $*r*_{*i*}$ ($1 ≤ *l* ≤ *r* ≤ 10^{1000}$). All numbers are given without the leading zeroes. Numbers in each line are separated by exactly one space character.

翻译中…

Output

翻译中…

Output $*t*$ lines. In each line print one integer — the answer for the corresponding segment modulo $1000000007$ ($10^{9} + 7$).

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Note

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In the first sample, the four nearly lucky numbers are 44, 47, 74, 77.

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In the second sample, only 74 and 77 are in the given segment.

翻译中…

样例

Input #1
1 2
1 100
Output #1
4
InputCopy OutputCopy
Input #2
1 2
70 77
Output #2
2
InputCopy OutputCopy
Input #3
2 1
1 20
80 100
Output #3
0
0
InputCopy OutputCopy
题目信息
题号
96E
时间限制
2 s
内存限制
256 MB

题面与样例版权归 Codeforces 及出题人所有;中文翻译由 AI 生成(CI 管线),如有出入请以原文为准。