How should I solve this challenge?

Question

What will be the output of the program?

float a = 0.7;

if(0.7 > a)
printf("Hi");
else
printf("Hello");

The answer is "Hi".
Some decimal numbers can't be represented with 100% accuracy in binary number system.
For example: 0.1 or 0.7 can't be, but 0.5, 0.25 can be.

How can I know this under 45 seconds? What would be the approach to solve this challenge?

Could you explain this snippet, step by step?

Answer 1

Here. Read these:

https://stackoverflow.com/questions/1839422/strange-output-in-comparison-of-float-with-float-literal

&

https://stackoverflow.com/questions/9850663/comparing-same-float-values-in-c

Answer 2

the answer is "Hi" because

0.7 is a double constant but variable "a" is float.

so whenever we compare a double with floats it leads to type promotion and hence double is greater than float

that's why 0.7 > a

approach to solve this problem

by default floating values have double precision. but if we want to use a value as float then we need to use the keyword "float"

here 0.7 (only) will be stored in memory with double precision and variable a = 0.7 will be stored as float and floats in double precision will be nearly equal to 0.7

see the code below

check it.....👇👇

https://code.sololearn.com/ch98HcDVBQLS/?ref=app