A. Roma and Lucky Numbers

A. Roma and Lucky Numbers
time limit per test
1 second
memory limit per test
256 megabytes
input
standard input
output
standard output

Roma (a popular Russian name that means 'Roman') loves the Little Lvov Elephant's lucky numbers.

Let us remind you that lucky numbers are positive integers whose decimal representation only contains lucky digits 4 and 7. For example, numbers 477444 are lucky and 517467 are not.

Roma's got n positive integers. He wonders, how many of those integers have not more than k lucky digits? Help him, write the program that solves the problem.

Input

The first line contains two integers nk (1 ≤ n, k ≤ 100). The second line contains n integers ai (1 ≤ ai ≤ 109) — the numbers that Roma has.

The numbers in the lines are separated by single spaces.

Output

In a single line print a single integer — the answer to the problem.

Sample test(s)
input
3 4
1 2 4
output
3
input
3 2
447 44 77
output
2

水题……
做的第一道CodeForce题
原文地址:https://www.cnblogs.com/liuxueyang/p/2860775.html