c - 当我打印我的字符串时，它打印的长度超过了它的长度

Question

我的代码

char str[100];
    scanf("%s\n",str);
    char str2[2];
    scanf("%c\n",&str2[0]);
    scanf("%c\n",&str2[1]);
    printf("%s",str2);

输入

abbcde
b
c

输出

bcabbcde

如果 str2 的长度为 2 只是为什么所有这些额外的东西来自，我已经检查了两个字符串的输入是否正确记录。

Answer 1

工作代码如下

#include <stdio.h>

int main()
{
    char str[100];
    scanf("%s",str);
    char str2[3];
    scanf(" %c",&str2[0]); 
    scanf(" %c",&str2[1]);
    str[2]='\0';
    printf("%s",str2);

    return 0;
}

修复 1:

Unrelated: trailing whitespace characters such as \n in scanf() -- @ex_nihilo already given a comment on this.

修复 2:

Space before %c removes any white space (blanks, tabs, or newlines)

修复 3:

If str2 is a string then the end character should be '\0' and we need to add this explicitly. For this we need to increase the size of str2 array to 3.