以下代码适用于所有正输入，但负值是伪造的。如果负值最初设置为0，它会起作用，因为它们会添加。最后的例子。
#include <stdio.h> /* Necessary header */
#define MAX_RESPONDENTS 6
#define MIN_RESPONSE_VALUE -100 /* Abbreviated MiRV */
#define MAX_RESPONSE_VALUE 86 /* Abbreviated MaRV */
#define RESPONSE_VALUE 187 /* Equals |(MiRV)| + or - |(MaRV)| + 1 */
#define STOP 3
#define BREAK 1
int main(void)
{
CountRating();
return 0;
}
CountRating()
{
int ratingCounters, rating[RESPONSE_VALUE] = {0}, Counter, response;
for (ratingCounters = 0; ratingCounters < MAX_RESPONDENTS;)
{
int response = ratingCounters, stop = STOP;
printf("Enter a integer rating between %d and %d for the product: ", MIN_RESPONSE_VALUE, MAX_RESPONSE_VALUE);
scanf("%d", &response);
if (response <= MAX_RESPONSE_VALUE && response >= MIN_RESPONSE_VALUE)
stop = STOP;
else
{
int stopElse = stop;
if (stopElse < BREAK)
break;
else
{
do
{
printf("\nNot within range. Try again.\nYou have %d more attempts before program outputs total:", stop);
scanf("%d", &response);
printf("\n");
--stop;
if (stop < BREAK)
break;
} while (response > MAX_RESPONSE_VALUE || response < MIN_RESPONSE_VALUE);
} if (stop < BREAK)
break;
}
++rating[response];
++ratingCounters;
}
printf("\nRating Number of Responses\n");
printf("------ -------------------");
for (Counter = MAX_RESPONSE_VALUE; Counter >= MIN_RESPONSE_VALUE; --Counter)
{
printf("\n%3d%24d", Counter, rating[Counter]);
}
}
示例输出：
Enter a integer rating between -100 and 86 for the product: 66
Enter a integer rating between -100 and 86 for the product: 66
Enter a integer rating between -100 and 86 for the product: 66
Enter a integer rating between -100 and 86 for the product: 66
Enter a integer rating between -100 and 86 for the product: 66
Enter a integer rating between -100 and 86 for the product: 55
Rating Number of Responses
------ -------------------
86 0
85 0
84 0
83 0
82 0
81 0
80 0
79 0
78 0
77 0
76 0
75 0
74 0
73 0
72 0
71 0
70 0
69 0
68 0
67 0
66 5
65 0
64 0
63 0
62 0
61 0
60 0
59 0
58 0
57 0
56 0
55 1
54 0
53 0
52 0
51 0
50 0
49 0
48 0
47 0
46 0
45 0
44 0
43 0
42 0
41 0
40 0
39 0
38 0
37 0
36 0
35 0
34 0
33 0
32 0
31 0
30 0
29 0
28 0
27 0
26 0
25 0
24 0
23 0
22 0
21 0
20 0
19 0
18 0
17 0
16 0
15 0
14 0
13 0
12 0
11 0
10 0
9 0
8 0
7 0
6 0
5 0
4 0
3 0
2 0
1 0
0 0
-1 55
-2 2686244
-3 2686244
-4 -3
-5 4206858
-6 4199517
-7 1965606432
-8 -2
-9 -533773290
-10 1965657301
-11 2686916
-12 1965975817
-13 2685900
-14 28
-15 2685972
-16 0
-17 2686720
-18 -1792050746
-19 1965606432
-20 1966156064
-21 1
-22 1965606483
-23 2685944
-24 17
-25 1965552124
-26 2685880
-27 1966146752
-28 1965532226
-29 2685868
-30 1966156064
-31 1
-32 0
-33 1966156064
-34 0
-35 28
-36 6105760
-37 1
-38 1965551966
-39 1965572357
-40 -2
-41 -533740746
-42 1965657301
-43 2685928
-44 1966156064
-45 2685768
-46 28
-47 1965572357
-48 0
-49 1966156064
-50 28
-51 -1792050874
-52 1965572357
-53 1
-54 1965572401
-55 2685816
-56 6097440
-57 1965552169
-58 2685752
-59 36
-60 1966146816
-61 0
-62 1966146816
-63 36
-64 0
-65 -1792050942
-66 1965552271
-67 1965552263
-68 2685756
-69 6105754
-70 4104
-71 4096
-72 6097428
-73 36
-74 -2
-75 358724962
-76 1999401429
-77 2685928
-78 -1
-79 2685472
-80 16777216
-81 6094848
-82 1
-83 0
-84 6105755
-85 6105760
-86 6095044
-87 8
-88 2
-89 1999167428
-90 1
-91 6095044
-92 -218103565
-93 2685640
-94 -254549010
-95 0
-96 1136989510
-97 -503245737
-98 2752512
-99 6098688
-100 0
Process returned 0 (0x0) execution time : 9.734 s
Press any key to continue.
答案 0 :(得分：3)
Rating是一个大小为187的数组。您正在索引负值，这意味着C在数组开始之前访问内存并打印存储在那里的任何垃圾值。您只能合法地访问0到186之间的值，因此您只需在访问和存储评级时向索引添加100即可。这样，数字-100对应于索引0，-99对应于索引1，等等。
答案 1 :(得分：2)
数组的索引始终从零开始。您不应传递数组的负索引。如果要使用负索引，请在索引中添加常量。
在您的示例代码中，您可以将-MIN_RESPONSE_VALUE添加到索引中，以便在您要访问索引rating[k - MIN_RESPONSE]时访问k。
答案 2 :(得分：1)
您的代码分配给数组的负索引。这通常不好 - 您只保留了0的内存：RESPONSE_VALUE-1，写入该范围之外的任何内容都会产生不可预测的后果。你有两个一般选择。一种是将范围MIN_RESPONSE_VALUE：MAX_RESPONSE_VALUE映射到0：（MAX_RESPONSE_VALUE-MIN_RESPONSE_VALUE）。即每当您对评级进行索引时减去MIN_RESPONSE_VALUE：
++rating[response-MIN_RESPONSE_VALUE];
另一个是重新回应，给它一个新的零点。这将使您不必一直减去MIN_RESPONSE_VALUE，但可能会让读者感到困惑：
rating -= MIN_RESPONSE_VALUE;
在for循环之前执行此操作。执行此操作后，等级[MIN_RESPONSE_VALUE]是一个有效的索引，即使它是负数。
答案 3 :(得分：1)
实际上负面指数是完全可以接受的。问题是你的索引会进入专用于堆栈数组的内存之外的区域。更改rating[-1]您在堆栈外更改堆栈并因此破坏它。难怪那些值没有用rating[RESPONSE_VALUE] = {0}初始化为零，再次它们在数组之外并在堆栈上显示一些数据。
答案 4 :(得分：0)
我花了一段时间，但我明白了。感谢。
#include <stdio.h> /* Necessary header */
#define MAX_RESPONDENTS 6
#define MIN_RESPONSE_VALUE -100 /* Abbreviated MiRV */
#define MAX_RESPONSE_VALUE 86 /* Abbreviated MaRV */
#define RESPONSE_VALUE 187 /* Equals |(MiRV)| + or - |(MaRV)| + 1 */
#define STOP 3
#define BREAK 1
#define DOUBLE_RESPONSE_VALUE 374
int main(void)
{
CountRating();
return 0;
}
CountRating()
{
int ratingCounters, rating[DOUBLE_RESPONSE_VALUE] = {0}, Counter, response;
for (ratingCounters = 0; ratingCounters < MAX_RESPONDENTS;)
{
int response = ratingCounters, stop = STOP;
printf("Enter a integer rating between %d and %d for the product: ", MIN_RESPONSE_VALUE, MAX_RESPONSE_VALUE);
scanf("%d", &response);
if (response <= MAX_RESPONSE_VALUE && response >= MIN_RESPONSE_VALUE)
stop = STOP;
else
{
int stopElse = stop;
if (stopElse < BREAK)
break;
else
{
do
{
printf("\nNot within range. Try again.\nYou have %d more attempts before program outputs total:", stop);
scanf("%d", &response);
printf("\n");
--stop;
if (stop < BREAK)
break;
} while (response > MAX_RESPONSE_VALUE || response < MIN_RESPONSE_VALUE);
} if (stop < BREAK)
break;
}
if (response < 0)
++rating[response + abs(RESPONSE_VALUE)];
else
++rating[response + abs(RESPONSE_VALUE)];
++ratingCounters;
}
printf("\nRating Number of Responses\n");
printf("------ -------------------");
for (Counter = MAX_RESPONSE_VALUE; Counter >= MIN_RESPONSE_VALUE; --Counter)
{
printf("\n%3d%24d", Counter, rating[Counter + (RESPONSE_VALUE)]);
}
}