c - 我已经编写了一个代码来将摄氏度转换为华氏度，但是输出太大了

Question

代码是:

#include <stdio.h>
#include <stdlib.h>

int main() {
    double C, F;
    printf("Enter the temperature in Celisius: ");
    scanf("%f", &C);
    F = 32 + (C * (180.0 / 100.0));
    printf("%f C = %f F\n", C, F);
    system("pause");
    return 0;
}

输出是:

Enter the temperature in Celisius: 100
-92559604910177974000000000000000000000000000000000000000000000.000000 C = -166607288838320360000000000000000000000000000000000000000000000.000000 F

Answer 1

scanf() 的 double 转换说明符错误。你需要使用

  scanf("%lf", &C);

要添加相关引用，来自 C11，第 §7.21.6.2 章

l (ell)

Specifies that a following d, i, o, u, x, X, or n conversion specifier applies to an argument with type pointer to long int or unsigned long
int; that a following a, A, e, E, f, F, g, or G conversion specifier applies to an argument with type pointer to double; or that a following c, s, or [ conversion specifier applies to an argument with type pointer to wchar_t.

也就是说，您必须检查scanf() 的返回值以确保调用成功。否则，您最终将使用未初始化变量的值。