A15168. Sort Zero
编程题
普及/提高-
知识点
题目描述
An array is sorted if it has no inversions
A Young Boy
You are given an array of $n$ positive integers $a_1,a_2,\ldots,a_n$ .
In one operation you do the following:
1. Choose any integer $x$ .
2. For all $i$ such that $a_i = x$ , do $a_i := 0$ (assign $0$ to $a_i$ ).
Find the minimum number of operations required to sort the array in non-decreasing order.
A Young Boy
You are given an array of $n$ positive integers $a_1,a_2,\ldots,a_n$ .
In one operation you do the following:
1. Choose any integer $x$ .
2. For all $i$ such that $a_i = x$ , do $a_i := 0$ (assign $0$ to $a_i$ ).
Find the minimum number of operations required to sort the array in non-decreasing order.
输入格式
Each test contains multiple test cases. The first line contains the number of test cases $t$ ( $1 \le t \le 10^4$ ). Description of the test cases follows.
The first line of each test case contains a single integer $n$ ( $1 \le n \le 10^5$ ).
The second line of each test case contains $n$ positive integers $a_1,a_2,\ldots,a_n$ ( $1 \le a_i \le n$ ).
It is guaranteed that the sum of $n$ over all test cases does not exceed $10^5$ .
The first line of each test case contains a single integer $n$ ( $1 \le n \le 10^5$ ).
The second line of each test case contains $n$ positive integers $a_1,a_2,\ldots,a_n$ ( $1 \le a_i \le n$ ).
It is guaranteed that the sum of $n$ over all test cases does not exceed $10^5$ .
输出格式
For each test case print one integer — the minimum number of operations required to sort the array in non-decreasing order.
输入输出样例
输入 #1
5 3 3 3 2 4 1 3 1 3 5 4 1 5 3 2 4 2 4 1 2 1 1
输出 #1
1 2 4 3 0
说明/提示
In the first test case, you can choose $x = 3$ for the operation, the resulting array is $[0, 0, 2]$ .
In the second test case, you can choose $x = 1$ for the first operation and $x = 3$ for the second operation, the resulting array is $[0, 0, 0, 0]$ .
In the second test case, you can choose $x = 1$ for the first operation and $x = 3$ for the second operation, the resulting array is $[0, 0, 0, 0]$ .