对于我的作业,用户输入 1 到 9 之间的 5 个整数来表示 5 个 9 面骰子,然后用它们来计算分数。我们还需要能够检测无效输入,即 1-9 之间 5 个整数以外的任何输入。问题是,当我为任务运行自动测试时,当输入少于 5 个内容时,我会收到运行时错误。
我的错误检查代码是(忽略 countArray 的东西,这是程序后面的内容):
#include <stdio.h>
#include <stdlib.h>
#define TRUE 1
#define FALSE 0
#define ARRAY_SIZE 5
...
int main(void) {
int numbers[ARRAY_SIZE];
int scanFail = 0;
int i = 0;
...
// Check for if 5 integers between 1 and 9 have been entered
while (i < ARRAY_SIZE && scanFail == FALSE) {
if (scanf("%d", &numbers[i]) != 1) {
scanFail = TRUE;
}
if (numbers[i] < 1 || numbers[i] > 9) {
scanFail = TRUE;
}
countArray[i] = ARRAY_NOT_COUNTED;
i++;
}
if (scanFail == TRUE) {
printf("Invalid Input: 5 integers 1..9 must be supplied.\n");
return EXIT_FAILURE;
}
...
这就是自动测试的内容:
Test10 (1 2 3) - failed (errors)
Your program produced these errors:
Runtime error: uninitialized variable accessed.
Execution stopped here in main() in youChew.c at line 65:
\t\t}
\t\t
-->\t\t if (numbers[i] < 1 || numbers[i] > 9) {
\t\t scanFail = TRUE;
\t\t}
Values when execution stopped:
i = 3
numbers = {1, 2, 3, 69513217, -22336628}
scanFail = 1
numbers[i] = 69513217
Test 11 (potato) - failed (errors)
Your program produced these errors:
Runtime error: uninitialized variable accessed.
Execution stopped here in main() in youChew.c at line 65:
\t\t}
\t\t
-->\t\t if (numbers[i] < 1 || numbers[i] > 9) {
\t\t scanFail = TRUE;
\t\t}
Values when execution stopped:
i = 0
numbers = {69515968, 0, 8192, 69513217, -18240628}
scanFail = 1
numbers[i] = 69515968
我不太确定如何修复它,因此非常感谢您的帮助。
最佳答案
恕我直言,立即打破循环通常会产生比维护标志更可读的代码..
在您的情况下,问题是如果 scanf 失败,您还没有读取该数字,但您想检查它(未初始化的值)是否在 1 到 9 之间。该测试甚至不应该发生。 快速失败。
关于c - 使用 scanf 进行错误检查,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/43542518/