从客户端获取 int 数字的 C 简单程序

Question

我是 C 语言新手。我想创建一个获取 2 int 并打印它们的总和的应用程序。我尝试使用 while 从客户端获取 int 数字，但我得到了无限的 while 循环。

int main()
{
    //printf("Hello world!\n");

    int x = 0, y = 0;
    printf("Insert 2 numvers \n");

    int status = scanf("%d", &x);
    while (status == 0) {
        printf("Error occured. Enter new number: \n");
        status = scanf("%d", &x);
    }

    scanf("%d", &y);

    printf("The sum is: %d", x + y);
    return 0;
}

输出(我没有插入另一个数字的选项):

Insert new number: 
ascsac -> input
Error occured. Enter new number:
Error occured. Enter new number:
Error occured. Enter new number:
Error occured. Enter new number:
Error occured. Enter new number:
Error occured. Enter new number:
Error occured. Enter new number:
Error occured. Enter new number:
Error occured. Enter new number:
(Endless loop).

Answer 1

如前所述，scanf 失败时会将输入保留在 stdin 中，循环中的下一个 scanf 将读取该输入并再次失败，导致无限循环。

可以使用一个旧的解决方案 -

 int c;
 int status = scanf("%d", &x);
 while (status == 0) {
    while((c=getchar())!=EOF && c!='\n');               //clear stdin before next scanf
    if(c==EOF) break;
    printf("Error occured. Enter new number: \n");
    status = scanf("%d", &x);
}