我想用c语言中的stack反转一个句子。
你怎么样。
我写了以下程序
#include<stdio.h>
#include<conio.h>
struct rev
{
char *var;
struct rev *next;
};
struct rev *top=NULL;
struct rev *temp,*test;
main()
{
int start, j = 0;
char *p="Hi, How are you? Hope everything is fine";
char *s;
char *t;
*t = '\0';
s = p;
while(1) {
if(*p == ' '|| *p == '\0') {
printf("Inside if \n");
*(t + j) = '\0';
printf("This is t %s\n",t);
if(top == NULL) {
temp = (struct rev *)malloc(sizeof(struct rev));
temp->next = NULL;
temp->var=t;
top = temp;
} else {
temp = (struct rev *)malloc(sizeof(struct rev));
printf("This is going in stack %s\n", t);
temp->var = t;
temp->next = top;
top = temp;
printf("This is top %s\n", top->var);
}
j = 0;
} else {
*(t+j) = *p;
printf("%c\n", *p);
j++;
}
if(*p == '\0') {
break;
}
//printf("%c",*p);
p++;
}
struct rev *show;
show = top;
while(show != NULL) {
printf("%s\n", show->var);
show = show->next;
}
getch();
}
它存储正确,但在遍历时只给出最后一个元素。
我想不出是什么问题。
这是我的输出窗口:-
最佳答案
首先,你的char *t
只是一个指针,让它指向malloced内存,然后继续。。。我不明白代码是怎么运行的。。。当t实际上指向垃圾时,您正在执行*(t + j)
。
在第一次查看时,您正在覆盖t
。。。在分析字符串之后。即您设置j = 0
并覆盖先前存储的字符串,并且您的struct rev
持有指向此t
的指针,因此
你将得到you? you? you?
作为输出。而不是让char *var
中的struct rev
指向t
。。您的char *var
指向一个malloced内存并执行strcpy
或strtok
我只是对你的代码做了一个粗略的修改,它在linux+gcc上对我有效。。。代码如下:
#include<stdio.h>
#include <stdlib.h>
struct rev
{
char *var;
struct rev *next;
};
struct rev *top=NULL;
struct rev *temp,*test;
main()
{
int start, j = 0;
char *p="How are you?";
char *s;
char *t;
t = malloc(1000);
if (t == NULL) {
//OUT OF MEMORY
exit(1);
}
s = p;
while(1) {
if(*p == ' '|| *p == '\0') {
printf("Inside if \n");
*(t + j) = '\0';
printf("This is t %s\n",t);
if(top == NULL) {
temp = (struct rev *)malloc(sizeof(struct rev));
temp->next = NULL;
temp->var = malloc(100);
if (temp->var == NULL) {
//OUT OF MEMORY
exit(1);
}
strcpy(temp->var, t);
top = temp;
} else {
temp = (struct rev *)malloc(sizeof(struct rev));
printf("This is going in stack %s\n", t);
temp->var = malloc(100);
if (temp->var == NULL) {
//OUT OF MEMORY
exit(1);
}
strcpy(temp->var, t);
temp->next = top;
top = temp;
printf("This is top %s\n", top->var);
}
j = 0;
} else {
*(t+j) = *p;
printf("%c\n", *p);
j++;
}
if(*p == '\0') {
break;
}
//printf("%c",*p);
p++;
}
struct rev *show;
show = top;
while(show != NULL) {
printf("%s\n", show->var);
show = show->next;
}
//getch();
}
输出如下:
H
o
w
Inside if
This is t How
a
r
e
Inside if
This is t are
This is going in stack are
This is top are
y
o
u
?
Inside if
This is t you?
This is going in stack you?
This is top you?
you?
are
How
注:我不理解你在实现代码的哪个部分。。。你正在使用list并告诉你想要一个堆栈。堆栈和列表是两种不同的数据结构。