CF1839A.The Good Array

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题目描述

You are given two integers nn and kk .

An array a1,a2,,ana_1, a_2, \ldots, a_n of length nn , consisting of zeroes and ones is good if for all integers ii from 11 to nn both of the following conditions are satisfied:

  • at least ik\lceil \frac{i}{k} \rceil of the first ii elements of aa are equal to 11 ,
  • at least ik\lceil \frac{i}{k} \rceil of the last ii elements of aa are equal to 11 .

Here, ik\lceil \frac{i}{k} \rceil denotes the result of division of ii by kk , rounded up. For example, 63=2\lceil \frac{6}{3} \rceil = 2 , 115=2.2=3\lceil \frac{11}{5} \rceil = \lceil 2.2 \rceil = 3 and 74=1.75=2\lceil \frac{7}{4} \rceil = \lceil 1.75 \rceil = 2 .

Find the minimum possible number of ones in a good array.

输入格式

Each test contains multiple test cases. The first line contains a single integer tt ( 1t1041 \le t \le 10^4 ) — the number of test cases.

The only line of each test case contains two integers nn , kk ( 2n1002 \le n \le 100 , 1kn1 \le k \le n ) — the length of array and parameter kk from the statement.

输出格式

For each test case output one integer — the minimum possible number of ones in a good array.

It can be shown that under the given constraints at least one good array always exists.

输入输出样例

  • 输入#1

    7
    3 2
    5 2
    9 3
    7 1
    10 4
    9 5
    8 8

    输出#1

    2
    3
    4
    7
    4
    3
    2

说明/提示

In the first test case, n=3n = 3 and k=2k = 2 :

  • Array [1,0,1][ \, 1, 0, 1 \, ] is good and the number of ones in it is 22 .
  • Arrays [0,0,0][ \, 0, 0, 0 \, ] , [0,1,0][ \, 0, 1, 0 \, ] and [0,0,1][ \, 0, 0, 1 \, ] are not good since for i=1i=1 the first condition from the statement is not satisfied.
  • Array [1,0,0][ \, 1, 0, 0 \, ] is not good since for i=1i=1 the second condition from the statement is not satisfied.
  • All other arrays of length 33 contain at least 22 ones.

Thus, the answer is 22 .

In the second test case, n=5n = 5 and k=2k = 2 :

  • Array [1,1,0,0,1][ \, 1, 1, 0, 0, 1 \, ] is not good since for i=3i=3 the second condition is not satisfied.
  • Array [1,0,1,0,1][ \, 1, 0, 1, 0, 1 \, ] is good and the number of ones in it is 33 .
  • It can be shown that there is no good array with less than 33 ones, so the answer is 33 .

In the third test case, n=9n = 9 and k=3k = 3 :

  • Array [1,0,1,0,0,0,1,0,1][ \, 1, 0, 1, 0, 0, 0, 1, 0, 1 \, ] is good and the number of ones in it is 44 .
  • It can be shown that there is no good array with less than 44 ones, so the answer is 44 .

In the fourth test case, n=7n = 7 and k=1k = 1 . The only good array is [1,1,1,1,1,1,1][ \, 1, 1, 1, 1, 1, 1, 1\, ] , so the answer is 77 .

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