C++ 无法理解 fgets 输出

请参考fgets documentation.

从给定的文件流中最多读取count-1个字符，并将它们存储在str指向的字符数组中.如果找到换行符，则解析停止，在这种情况下，字符串将包含换行符，或者如果出现文件结束.如果读取字节且未发生错误，则在紧接写入str的最后一个字符之后的位置写入一个空字符.

您的电话最多只能阅读n-1个字符.具有三个字节空间的char数组只能容纳两个字符的字符串，因为需要空终止符才能使其成为有效的字符串.

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

int main(void) {
    // Ask the user to enter how many characters you want to write.
    printf("Enter how many characters you want to write. \n");
    int n;
    int itemsRead = scanf_s("%d", &n);

    if (itemsRead != 1) {
        // scanf didn't read the expected input, handle the error
        printf("Error: Input is not in the expected format.\n");
        return 1; // Return a non-zero value to indicate an error
    }

    // Increment n by one to allow for the null terminator.
    ++n;
    
    // Clear the input buffer
    int c;
    while ((c = getchar()) != '\n' && c != EOF);

    char* string = NULL;
    string = (char*)malloc(n * sizeof(char));
    // Equivalent to:
    // string = (char*)malloc(n);
    // Because sizeof(char) == 1

    if (string != NULL) {
        printf("Enter the string \n");
        fgets(string, n, stdin);
        printf("string is: %s\n", string);
    }

    free(string);
    string = NULL;
}