Question

我编写了以下程序，但每次运行时，for循环都不起作用，直到我输入另一个数字。然后使用输入的第二个数字运行for循环。为什么会这样？似乎没有人遇到这个问题......这是程序：

#include <stdio.h>
#include <math.h>

int main(void)
{

float limit;
float count;
float series1, series2;

printf("Enter a limit for the series ");
scanf ("%f", &limit);
while (scanf ("%f", &limit) == 1) 
{
    for (series1 = 1, count = 2; count <= limit; count++)
            series1 += 1.0/count;
            printf ("\nThe sum of the first infinite series is %.4f", series1);
    for (series2 = 1, count = 2; count <= limit; count++)
            series2 += (1.0/count) * pow ((-1),(count - 1));
            printf ("\nThe sum of the second infinite series is %.4f", series2);

        printf("\n\nEnter a limit for the series (q to quit) ");
        scanf ("%f", &limit);
}
return 0;

}

Answer 1

你的问题就在这里：

scanf ("%f", &limit);
while (scanf ("%f", &limit) == 1)

while循环将在每次启动时执行该scanf，因此只丢失第一个scanf。

Answer 2

当你运行while循环while (scanf ("%f", &limit) == 1)时，它已经运行了scanf ("%f", &limit) == 1。尝试设置第一个scanf以输出变量并在while循环中运行变量。

程序运行但要求输入两次

2 个答案: