Today I have done leetcode's June LeetCoding Challenge with cpp.

June LeetCoding Challenge 10

Description

Height Checker

A school is trying to take an annual photo of all the students. The students are asked to stand in a single file line in non-decreasing order by height. Let this ordering be represented by the integer array expected where expected[i] is the expected height of the ith student in line.

You are given an integer array heights representing the current order that the students are standing in. Each heights[i] is the height of the ith student in line (0-indexed).

Return the number of indices where heights[i] != expected[i].

Example 1:

Input: heights = [1,1,4,2,1,3]
Output: 3
Explanation: 
heights:  [1,1,4,2,1,3]
expected: [1,1,1,2,3,4]
Indices 2, 4, and 5 do not match.

Example 2:

Input: heights = [5,1,2,3,4]
Output: 5
Explanation:
heights:  [5,1,2,3,4]
expected: [1,2,3,4,5]
All indices do not match.

Example 3:

Input: heights = [1,2,3,4,5]
Output: 0
Explanation:
heights:  [1,2,3,4,5]
expected: [1,2,3,4,5]
All indices match.

Constraints:

• 1 <= heights.length <= 100
• 1 <= heights[i] <= 100

Solution

class Solution {
public:
  int heightChecker(vector<int>& heights) {
    vector<int> newHeights(heights.begin(), heights.end());
    sort(newHeights.begin(), newHeights.end());
    int answer = 0;
    for(int i = 0; i < heights.size(); ++i) {
      answer += heights[i] != newHeights[i];
    }
    return answer;
  }
};