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# # 1051 Height Checker

[LeetCode](https://leetcode.com/problems/height-checker/)

```
Students are asked to stand in non-decreasing order of heights for an annual photo.

Return the minimum number of students not standing in the right positions. 
(This is the number of students that must move in order for 
all students to be standing in non-decreasing order of height.)

input: 沒排序的數字陣列
out: 哪幾個人沒在對的位置上
```

```
Example 1:

Input: [1,1,4,2,1,3]
Output: 3
Explanation: 
Students with heights 4, 3 and the last 1 are not standing in the right positions.
 

Note:

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

/**
 * @param {number[]} heights
 * @return {number}
 */
var heightChecker = function(heights) {}
```

### 怎麼解

跟排序好的陣列比較

```
[1,1,4,2,1,3]
[1,1,1,2,3,4]
```

```
var heightChecker = function(heights) {
    let sortH = [...heights];
    sortH.sort( (a, b) => a-b );
    let count = 0;
  
    heights.forEach((item, index) => {
        if(item !=sortH[index]){
            count ++;
        }
    })
    return count;
};

console.log(heightChecker([1,1,4,2,1,3]))
// faster than 99.17% of JavaScript online submissions
```