Sifid and Strange Subsequences

A sequence (b1,b2,…,bk) is called strange, if the absolute difference between any pair of its elements is greater than or equal to the maximum element in the sequence. Formally speaking, it’s strange if for every pair (i,j) with 1≤i<j≤k, we have |ai−aj|≥MAX, where MAX is the largest element of the sequence. In particular, any sequence of length at most 1 is strange.

For example, the sequences (−2021,−1,−1,−1) and (−1,0,1) are strange, but (3,0,1) is not, because |0−1|<3.

Sifid has an array a of n integers. Sifid likes everything big, so among all the strange subsequences of a, he wants to find the length of the longest one. Can you help him?

A sequence c is a subsequence of an array d if c can be obtained from d by deletion of several (possibly, zero or all) elements.

Input
The first line contains an integer t (1≤t≤104) — the number of test cases. The description of the test cases follows.

The first line of each test case contains an integer n (1≤n≤105) — the length of the array a.

The second line of each test case contains n integers a1,a2,…,an (−109≤ai≤109) — the elements of the array a.

It is guaranteed that the sum of n over all test cases doesn’t exceed 105.

Output
For each test case output a single integer — the length of the longest strange subsequence of a.

Example
inputCopy
6
4
-1 -2 0 0
7
-3 4 -2 0 -4 6 1
5
0 5 -3 2 -5
3
2 3 1
4
-3 0 2 0
6
-3 -2 -1 1 1 1
outputCopy
4
5
4
1
3
4
Note
In the first test case, one of the longest strange subsequences is (a1,a2,a3,a4)
In the second test case, one of the longest strange subsequences is (a1,a3,a4,a5,a7).

In the third test case, one of the longest strange subsequences is (a1,a3,a4,a5).

In the fourth test case, one of the longest strange subsequences is (a2).

In the fifth test case, one of the longest strange subsequences is (a1,a2,a4).

我认识每一个字，就是读不懂题。
本题大意：一个符合标准的数列就是将其中任意一对数的差值的绝对值小于该数列的最大值，我们可以去掉数列中的任意元素来达到这个目的。
解法：首先如果一个数列都是负数，那么肯定会满足，所以我们根本不需要考虑负数的问题，0也是，我们只需要考虑正数，正数如果存在，那么它必须只有一个，因为如果两个正数相减永远不会比其中一个正数大，而且这个正数还不能比任意两个负数相减的差值的绝对值大。

#include<iostream>
#include <cstdio>
#include <algorithm>
using namespace std;
long long fab(long long x)//取绝对值
{if (x < 0)return (-x);else return x;
}
int main()
{int t, n;int a[100001];int b[100001];scanf_s("%d", &t);while (t--){scanf_s("%d", &n);int ans = 0;int cnt = 0;for (int i = 1; i <= n; i++){scanf_s("%d", &a[i]);ans += a[i] <= 0;if (a[i] <= 0)b[++cnt] = a[i];}sort(b + 1, b + cnt + 1);long long temp = 10000000000;for (int i = 1; i < cnt; i++)temp = min(temp, fab(b[i] - b[i + 1]));for (int i = 1; i <= n; i++)if (a[i] > 0 && a[i] <= temp){++ans;break;}printf("%d\n", ans);}return 0;
}

return code;

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