c/c++ 字符转换

Question

输入a b输出为什么会有一个10结尾呢？
输出为：

97
a
32
 
98
b
10

#include <iostream>
#include <stdio.h>
using namespace std;
int main()
{
    int chr;
    while ((chr = getchar()) != EOF)
    {
        cout<<chr<<endl;
        if (char(chr))
        {
            cout<<char(chr)<<endl;
        }
    }

    return 0;
}

Answer 1

When you enter 97 and then retract, you actually entered three characters: 9, 7, newline, so the following output will appear:
97
57 -> ASCII code of the number 9
9 -> Number 9 character
55 -> Number 7 ASCII code
7 -> Number 7 character
10 -> Line break ASCII code
-> Here is a Line break

Answer 2

Generally, you need to add a get() to remove the newline character