Confusion with scanf() or if() - c

Question

I am not so familiar with C. Therefore, maybe someone will easily find a solution, I will not mind if you share it.
After entering the data in the first scanf() always gives the option else(): "Error".
I was looking for possible options for the problem. I found a lot of things like that, but nothing that to help me specifically. I think the mistake is in the strcmp(). But I can not say for sure. Will you help?
#include <stdio.h>
#include <string.h>
int main()
{
float celsius, fahrenheit;
char tempConvering[10];
printf("Enter what to convert to what (F to C; C to F): ");
scanf(" %s", &tempConvering[10]);
if(strcmp(tempConvering, "F to C") == 0)
{
printf("\nEnter temperature in Fahrenheit: ");
scanf(" %f", &fahrenheit);
celsius = fahrenheit * 1.8 + 32;
printf("%.2f Fahrenheits = %.2f Celsius\n", fahrenheit, celsius);
}
else if(strcmp(tempConvering, "C to F") == 0)
{
printf("\nEnter temperature in Celsius: ");
scanf(" %f", &celsius);
celsius = (fahrenheit - 32) / 1.8;
printf("%.2f Celsius = %.2f Fahrenheits\n", celsius, fahrenheit);
}
else
{
puts("\nError!");
}
}

Answer 1

I believe there's an error with how you're using scanf, specifically, at this point:
scanf(" %s", &tempConvering[10]);
^
|
+---- here
The second argument to scanf should be the address of the place to store the result. Here, you're saying "place the string that's read in in the memory just after the buffer that I've set up," which isn't probably want you wanted to do. Instead, write this:
scanf(" %s", tempConvering);
This says "place the string inside the buffer named tempConverting." If you're just getting started with C and haven't learned much about pointers and arrays, a good rule of thumb is that if you're reading a string with `scanf, you should just give the name of the array variable where you want to store the string rather than using an ampersand.
Hope this helps!

Answer 2

#include <stdio.h>
#include <string.h>
int main()
{
float celsius, fahrenheit;
char tempConvering[20];
printf("what do you want to convert? ");
scanf("%s", tempConvering);
if(strcmp(tempConvering, "Fahrenheits") == 0)
{
printf("Enter temperature in Fahrenheit: ");
scanf("%f", &fahrenheit);
celsius = (fahrenheit - 32) / 1.8;
printf("%.2f Fahrenheits = %.2f Celsius\n", fahrenheit, celsius);
}
else if(strcmp(tempConvering, "Celsius") == 0)
{
printf("Enter temperature in Celsius: ");
scanf("%f", &celsius);
fahrenheit = celsius * 9 / 5 + 32;
printf("%.2f Celsius = %.2f Fahrenheits\n", celsius, fahrenheit);
}
else
{
puts("\nError!");
}
}
This was the answer. I have to thank you for the tips, I will try to remember all the details about the scanf(). However, the problem disappeared only when I changed the desired answer not to "F to C" but to "Fahrenheits". Well, respectively, I changed the question. The program instantly earned. Nevertheless, attempts to do something with the scanf() are unsuccessful, to the extent that the same thing happens with the fgets().
In any case, somehow the problem is solved, thank you all!

Answer 3

Don't put extra space while you execute the scanf() function.
This might be an issue sometimes!
This should work fine:
scanf("%s", tempConvering);
By the way, while you take a string as an input, there is no need to use & before the string name.
Someone has already described the details above.