Anyone know why this code always returns 33.80?

Asked Jan 29 '22 at 17:36

Active Jan 29 '22 at 17:57

Viewed 41 times

int main()
{
    double tempc;
    printf("Enter your temperature (Celsius):\n");
    scanf("%f", &tempc);
    printf("Your temperature in Fahrenheit is %.2f", (1.8 + tempc + 32));
}

No matter what input I give to tempc it always prints 33.80? I am very confused.

edited Jan 29 '22 at 17:39

user17732522

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asked Jan 29 '22 at 17:36

Edward Roy

5

Your compiler should tell you the reason: https://godbolt.org/z/P5fnzzvzr `scanf` needs `%lf` to read a `double`. – mch Jan 29 '22 at 17:39
1

`scanf("%f", &tempc);` ==> `scanf("%lf", &tempc);` and turn up the warnings to 11. – Weather Vane Jan 29 '22 at 17:39
3

Aside: and fix the calculation error to be `1.8 * tempc + 32` – Weather Vane Jan 29 '22 at 17:41
3

Enable warnings and the compiler will tell you about the problem. For GCC/Clang for example: `-Wall -Wextra` – user17732522 Jan 29 '22 at 17:41
And add `-Werror`; then you won't by tempted to run buggy code. – Jonathan Leffler Jan 29 '22 at 17:59

Anyone know why this code always returns 33.80?

0 Answers0