CS50 (pset2) - 打印出首字母缩写的 C 程序中的行为不被理解

Question

我之前有使用 Python 的经验，但在 C 方面绝对是初学者。我正在研究 CS50x pset2 缩写(不太舒服)，其中一个简单的 C 程序应该接受由用户并打印出姓名的首字母。

当我运行该程序时，它似乎适用于某些情况，但对于某些名称，它会在末尾附加错误的“B”字符。这是代码:

#include <stdio.h>
#include <cs50.h>
#include <string.h>

string get_initials(string name, char initials[]);

int main(void)
{
    // user input (full name)
    printf("Please type your name: ");
    string name = get_string();

    // get the user name initials
    char initials[10];
    get_initials(name, initials);  // in: full name; out: initials
    printf("Initials: %s\n", initials);

}

string get_initials(string name, char initials[])
{
    int counter = 0;

    // Iterate over all characters
    for (int i = 0, n = strlen(name); i < n; i++)
    {
        // in case the i-th char is ' ', appends next char to the initials array
        if (name[i] == ' ')
        {
            initials[counter] = name[i+1];
            counter++;
        }
        // appends the first char to the initials array
        else if (i == 0)
        {
            initials[counter] = name[i];
            counter++;
        }
    }
    return initials;
}

这里是一些终端输出:

~/workspace/pset2/ $ ./initials
Please type your name: John Smith
Initials: JSB
~/workspace/pset2/ $ ./initials
Please type your name: John Smith Here
Initials: JSH
~/workspace/pset2/ $ ./initials
Please type your name: John
Initials: J
~/workspace/pset2/ $ ./initials
Please type your name: John Smith Here Again
Initials: JSHAB
~/workspace/pset2/ $ ./initials
Please type your name: John Smith Here Again Where
Initials: JSHAW
~/workspace/pset2/ $ ./initials
Please type your name: John Smith Here Again Where Here
Initials: JSHAWH
~/workspace/pset2/ $ 

我debugged for "John Smith"但仍然不明白为什么它附加 S\320\330B 而不是仅仅 S。

Answer 1

在get_initials函数的末尾，终止字符串:

...
initials[counter] = '\0';
return initials;