图书馆管理程序打印的意外随机字符

Question

我正在做一个学校项目，我必须制作一个程序，让用户输入有关新书的信息、删除书籍或显示所有已注册的书籍。

意外的行为是当我选择显示所有书籍时：第二本书的标题总是打印一些奇怪的随机字符或大约 15 个空行，而其余的保持正常。

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

typedef struct {
    int Pages,RlsYear,AtrNbr; //"Pages" stands for "the number of pages", "RlsYear" stands for "Release Year"
    char Title[128],Genre[128],Authors[256];
}book;

int main()
{
    int i,nb;
    char ch1,Tmp[128],cln; 
    book* b = malloc(1 * sizeof(book));

    nb=0;
    puts("\n Enter your choice : ");
    ch1=getch();

    while (ch1 != EOF && ch1 != 'q')
    {
        switch(ch1) {
            case 'n': // N to enter a new book
            case 'N':
            {
                printf("\n enter the book's Title : ");
                gets(b[nb].Title);
                printf(" enter the book's Genre : ");
                gets(b[nb].Genre);
                printf(" how many pages does the book have ? ");
                scanf("%d",&b[nb].Pages);
                gets(cln); //i added those "gets(cln)" to avoid problems from "scanf" so you can just ignore them
                printf(" when was the book released (year)? ");
                scanf("%d",&b[nb].RlsYear);
                gets(cln);
                printf(" how many authors does this book have ? ");
                scanf("%d",&b[nb].AtrNbr);
                gets(cln);
                strcpy(b[nb].Authors,"");

                for(i=0;i<b[nb].AtrNbr;i++)
                {
                    printf("\t\t enter the %d author : ",i+1);
                    gets(Tmp);
                    strcat(b[nb].Authors,Tmp);
                    strcat(b[nb].Authors," | ");
                }
                nb=nb+1;
                book* B = realloc(b, nb+1 * sizeof(book));
                b = B;
            }
            break;

            case 'i': // I to display registered books
            case 'I':
            {
                for(i=0;i<nb;i++)
                    printf("\n %s",b[i].Title);
            }
            break;

             default:
                 printf("unknown choice !");
                 break;
        }
        puts("\n Enter your choice : ");
        ch1=getch();
    }
    return 0;
}

Answer 1

当我将 b.Title 大小从 128 更改为 60 时，我解决了这个问题。显然，当 b.Title 大小超过 80 时，问题就出现了。有人可以解释一下吗？我现在更糊涂了

图书馆管理程序打印的意外随机字符

Unexpected random characters printed by library management program

c

structure