winter_course_Question_gdb_test2

xu6wu6gj@kmtath:~/2016-winter-course/test1$ gdb swap
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Reading symbols from swap...done.
(gdb) l
126	
127	
128	
129	return head;
130	
131	
132	
133	}
134	
135	int main(){return 0;}
(gdb) b 135
Breakpoint 1 at 0x40072a: file swap.c, line 135.
(gdb) r
Starting program: /home/xu6wu6gj/2016-winter-course/test1/swap 

Breakpoint 1, main () at swap.c:135
135	int main(){return 0;}
(gdb) p $head = (List*)malloc(sizeof(List))
$1 = (List *) 0x602010
(gdb) p $head->value = 1
$2 = 1
(gdb) p $head->next = (List*)malloc(sizeof(List))
$3 = (struct List_node *) 0x602030
(gdb) p $head->next->value = 2
$4 = 2
(gdb) p $head->next->next = (List*)malloc(sizeof(List))
$5 = (struct List_node *) 0x602050
(gdb) p $head->next->next->value = 3
$6 = 3
(gdb) p $head->next->next->next = (List*)malloc(sizeof(List))
$7 = (struct List_node *) 0x602070
(gdb) p $head->next->next->next->value = 4
$8 = 4
(gdb) p $head->next->next->next->next
$9 = (struct List_node *) 0x0

/*
初始化四個node的linked list  1 2 3 4  1為head
*/

(gdb) p $head->value
$10 = 1
(gdb) p $head->next->value
$11 = 2
(gdb) p $head->next->next->value
$12 = 3
(gdb) p $head->next->next->next->value
$13 = 4
(gdb) p $head->next->next->next->next
$14 = (struct List_node *) 0x0

/*
確定create出來是 1 2 3 4這樣的linked list
*/

(gdb) p $head = swap($head,$head,$head->next->next->next)
$15 = (List *) 0x602070

/*
交換 1  4 node
*/

(gdb) p $head->value
$16 = 4
(gdb) p $head->next->value
$17 = 2
(gdb) p $head->next->next->value
$18 = 3
(gdb) p $head->next->next->next->value
$19 = 1
(gdb) p $head = swap($head,$head->next->next->next,$head)
$20 = (List *) 0x602010

/*
交換 4  1
*/

(gdb) p $head->value
$21 = 1
(gdb) p $head->next->value
$22 = 2
(gdb) p $head->next->next->value
$23 = 3
(gdb) p $head->next->next->next->value
$24 = 4
(gdb) p $head->next->next->next->next
$25 = (struct List_node *) 0x0
(gdb) $head = swap($head,$head->next,$head->next->next)
Undefined command: "$head".  Try "help".
(gdb) p $head = swap($head,$head->next,$head->next->next)
$26 = (List *) 0x602010

/*
交換  2  3
*/

(gdb) p $head->value
$27 = 1
(gdb) p $head->next->value
$28 = 3
(gdb) p $head->next->next->value
$29 = 2
(gdb) p $head->next->next->next->value
$30 = 4
(gdb) p $head = swap($head,$head->next,$head->next->next)
$31 = (List *) 0x602010

/*
交換  2  3
*/

(gdb) p $head->value
$32 = 1
(gdb) p $head->next->value
$33 = 2
(gdb) p $head->next->next->value
$34 = 3
(gdb) p $head->next->next->next->value
$35 = 4
(gdb) p $head = swap($head,$head->next,$head->next->next->next)
$36 = (List *) 0x602010

/*
交換  2  4
*/

(gdb) p $head->value
$37 = 1
(gdb) p $head->next->value
$38 = 4
(gdb) p $head->next->next->value
$39 = 3
(gdb) p $head->next->next->next->value
$40 = 2
(gdb) p $head = swap($head,$head->next,$head->next->next->next)
$41 = (List *) 0x602010

/*
交換回來
*/

(gdb) p $head = swap($head,$head,$head->next)
$42 = (List *) 0x602030

/*
交換  1  2
*/

(gdb) p $head->value
$43 = 2
(gdb) p $head->next->value
$44 = 1
(gdb) p $head->next->next->value
$45 = 3
(gdb) p $head->next->next->next->value
$46 = 4
(gdb) p $head = swap($head,$head->next->next,$head->next->next->next)
$47 = (List *) 0x602030
(gdb) p $head->value
$48 = 2
(gdb) p $head->next->value
$49 = 1
(gdb) p $head->next->next->value
$50 = 4
(gdb) p $head->next->next->next->value
$51 = 3
(gdb) p $head = swap($head,$head,$head->next->next->next->next)
$52 = (List *) 0x602030
(gdb) p $head->value
$53 = 2
(gdb) p $head->next->value
$54 = 1
(gdb) p $head->next->next->value
$55 = 4
(gdb) p $head->next->next->next->value
$56 = 3

/*
以下是選第二個node當head  弄成三個node的 linked list  來測試
*/

(gdb) set $head2 = $head->next
(gdb) p $head2 = swap($head2,$head,$head2)
$57 = (List *) 0x602010
(gdb) p $head2->value
$58 = 1
(gdb) p $head2->next->value
$59 = 4
(gdb) p $head2->next->next->value
$60 = 3
(gdb) p $head2->next->next->next->value
Cannot access memory at address 0x0

看到最後  要print value很煩  node很多要打很多字  所以預計會補上print 函數來幫忙測試